Brexit: All you need to know about the UK leaving the EU
As the UK and the EU begin official talks on leaving, here is an easy-to-understand guide to Brexit - beginning with the basics, then a look at the negotiations, followed by a selection of answers to questions we've been sent.
What does Brexit mean?
It is a word that has become used as a shorthand way of saying the UK leaving the EU - merging the words Britain and exit to get Brexit, in a same way as a possible Greek exit from the euro was dubbed Grexit in the past.
Why is Britain leaving the European Union?
A referendum - a vote in which everyone (or nearly everyone) of voting age can take part - was held on Thursday 23 June, 2016, to decide whether the UK should leave or remain in the European Union. Leave won by 51.9% to 48.1%. The referendum turnout was 71.8%, with more than 30 million people voting.
Find the result in your area
What was the breakdown across the UK?
England voted for Brexit, by 53.4% to 46.6%. Wales also voted for Brexit, with Leave getting 52.5% of the vote and Remain 47.5%. Scotland and Northern Ireland both backed staying in the EU. Scotland backed Remain by 62% to 38%, while 55.8% in Northern Ireland voted Remain and 44.2% Leave. See the results in more detail.
What changed in government after the referendum?
Britain got a new Prime Minister - Theresa May. The former home secretary took over from David Cameron, who announced he was resigning on the day he lost the referendum. Like Mr Cameron, Mrs May was against Britain leaving the EU but she played only a very low-key role in the campaign and was never seen as much of an enthusiast for the EU. She became PM without facing a full Conservative leadership contest after her key rivals from what had been the Leave side pulled out.
Where does she stand on Brexit?
Theresa May had been against Brexit during the referendum campaign but is now in favour of it because she says it is what the British people want. Her key message has been that "Brexit means Brexit" and she triggered the two year process of leaving the EU on 29 March. She set out her negotiating goals in a letter to the EU council president Donald Tusk.
Why did she call a general election?
Theresa May became prime minister after David Cameron resigned, so had not won her own election. She ruled out calling a snap election when she moved into Downing Street, saying the country needed a period of stability after the upheaval of the Brexit vote. She said she was happy to wait until the next scheduled election in 2020.
But she surprised everyone after the Easter Bank Holiday by announcing that she had changed her mind with an election being called for Thursday, 8 June 2017.
The reason she gave was that she needed to strengthen her hand in Brexit negotiations with European leaders. She feared Labour, the SNP and other opposition parties - and members of the House of Lords - would try to block and frustrate her strategy, making the country look divided to other EU leaders and making her government look weak.
What happened in the election?
Mrs May's gamble backfired and she lost her overall majority and ended up with fewer MPs than before the campaign, meaning she no longer has enough Conservative MPs to guarantee winning votes in the House of Commons.
Because of that she is doing a deal with Northern Irish party the Democratic Unionists, which has 10 MPs, to enable her to form a minority government. The DUP are also in favour of Brexit but want to maintain the free-flowing border with EU member state the Republic of Ireland, which could mean continued membership of the customs union, the free trade area within the EU.
According to her own election message - when she urged people to vote for her to give her a bigger majority and more strength in the Brexit negotiations - Mrs May's hand is now weakened and she is vulnerable to being pushed about by MPs on different sides of the debate, when they come to vote on any divorce deal. She has said she wants to remain as prime minister to provide stability and certainty.
Will Brexit talks be delayed?
No. They have started as scheduled on 19 June. Here's a picture from that first session:
What if Theresa May's government falls and Labour gains power?
Brexit would still go ahead. Labour leader Jeremy Corbyn has ruled out a second referendum - but he has said MPs will get a decisive say on the final Brexit agreement with the EU, which means the UK might try to go back to the negotiating table to push for a better deal.
The Liberal Democrats, who have 12 out of 650 MPs, are against a "hard Brexit" (see below) and have promised a second referendum on the terms of any deal, in which they would campaign to stay in the EU. They have also ruled out any coalition deals with Labour or the Conservatives.
SNP leader Nicola Sturgeon has been pushing for Scotland - which voted to remain in the EU - to have a special status after Brexit, including remaining in the single market. She has called for a second independence referendum before the Brexit package has been finalised.
What about the economy, so far?
David Cameron, his Chancellor George Osborne and many other senior figures who wanted to stay in the EU predicted an immediate economic crisis if the UK voted to leave. House prices would fall, there would be a recession with a big rise in unemployment - and an emergency Budget would be needed to bring in the large cuts in spending that would be needed.
The pound did slump the day after the referendum - and remains around 15% lower against the dollar and 10% down against the euro - but the predictions of immediate doom have not proved accurate with the UK economy estimated to have grown 1.8% in 2016, second only to Germany's 1.9% among the world's G7 leading industrialised nations.
Inflation has risen - to 2.6% in April - its highest rate for three and a half years, but unemployment has continued to fall, to stand at an 11 year low of 4.8%. Annual house price increases have fallen from 9.4% in June but were still at an inflation-beating 4.1% in March, according to official ONS figures.
What is the European Union?
The European Union - often known as the EU - is an economic and political partnership involving 28 European countries (click here if you want to see the full list). It began after World War Two to foster economic co-operation, with the idea that countries which trade together are more likely to avoid going to war with each other.
It has since grown to become a "single market" allowing goods and people to move around, basically as if the member states were one country. It has its own currency, the euro, which is used by 19 of the member countries, its own parliament and it now sets rules in a wide range of areas - including on the environment, transport, consumer rights and even things such as mobile phone charges. Click here for a beginners' guide to how the EU works.
What is Article 50?
Article 50 is a plan for any country that wishes to exit the EU. It was created as part of the Treaty of Lisbon - an agreement signed up to by all EU states which became law in 2009. Before that treaty, there was no formal mechanism for a country to leave the EU.
It's pretty short - just five paragraphs - which spell out that any EU member state may decide to quit the EU, that it must notify the European Council and negotiate its withdrawal with the EU, that there are two years to reach an agreement - unless everyone agrees to extend it - and that the exiting state cannot take part in EU internal discussions about its departure. You can read more about Article 50 here.
What date will the UK will leave the EU?
For the UK to leave the EU it had to invoke Article 50 of the Lisbon Treaty which gives the two sides two years to agree the terms of the split. Theresa May triggered this process on 29 March, meaning the UK is scheduled to leave on Friday, 29 March 2019. It can be extended if all 28 EU members agree.
What's going to happen to all the EU laws in force in the UK?
The Conservatives will enact a Great Repeal Bill, if they win the general election. This will end the primacy of EU law in the UK. This Great Repeal Bill is supposed to incorporate all EU legislation into UK law in one lump, after which the government will decide over a period of time which parts to keep, change or remove.
Labour has said they will scrap the Great Repeal Bill if they win the election and replace it with an EU Rights and Protections Bill, which will copy across all EU law into UK law but make sure it cannot be changed or scrapped. The party says it wants to keep EU laws on workers rights, consumer rights and the environment.
What was the Supreme Court Brexit case about?
After a court battle, the UK's Supreme Court ruled in January that Parliament had to be consulted before Article 50 was invoked. That was why a two line Brexit bill went through Parliament. MPs approved it after Labour MPs were told to support it. But it was amended in the House of Lords to include a call to guarantee the rights of EU citizens already in the UK and to ensure a "meaningful vote" for Parliament before any Brexit deal was agreed with the EU. MPs reversed those changes and the unamended bill became law after the Lords backed down, with Labour peers dropping their backing for the changes. That cleared the way for Mrs May to send her letter to the EU officially announcing that the UK was leaving.
Who is going to negotiate Britain's exit from the EU?
Theresa May set up a government department, headed by veteran Conservative MP and Leave campaigner David Davis, to take responsibility for Brexit. Former defence secretary, Liam Fox, who also campaigned to leave the EU, was given the new job of international trade secretary and Boris Johnson, who was a leader of the official Leave campaign, is foreign secretary. These three are each set to play roles in negotiations with the EU and seek out new international agreements, although it would be Mrs May, as prime minister, who would have the final say. Who's who guide to both sides' negotiators.
How long will it take for Britain to leave the EU?
Once Article 50 is triggered, the UK has two years to negotiate its withdrawal. But no one really knows how the Brexit process will work - Article 50 was only created in late 2009 and it has never been used. Former Foreign Secretary Philip Hammond, who was appointed chancellor by Theresa May, wanted Britain to remain in the EU during the referendum campaign and suggested it could take up to six years for the UK to complete exit negotiations. The terms of Britain's exit will have to be agreed by 27 national parliaments, a process which could take some years, he has argued.
EU law still stands in the UK until it ceases being a member. The UK will continue to abide by EU treaties and laws, but not take part in any decision-making.
Why will Brexit take so long?
Unpicking 43 years of treaties and agreements covering thousands of different subjects was never going to be a straightforward task. It is further complicated by the fact that it has never been done before and negotiators will, to some extent, be making it up as they go along. The post-Brexit trade deal is likely to be the most complex part of the negotiation because it needs the unanimous approval of more than 30 national and regional parliaments across Europe, some of whom may want to hold referendums.
The likely focus of negotiations between the UK and EU
Theresa May has made it clear that the UK will not seek to stay in the EU single market, but that strategy has now been put in doubt by the general election result, with some of her MPs - and the strengthened opposition Labour Party - thought to be against it. Labour has said it wants the UK to retain all the benefits of being in the single market, even though it does not necessarily have be a member. Staying in the single market mean the UK staying under the auspices of the European Court of Justice and having to allow unlimited EU immigration, under freedom of movement rules. We found out more detail about Mrs May's negotiating priorities in the letter officially triggering the process of the leaving the EU on 29 March. Here's a guide to the key points.
Mrs May says she wants the UK to reach a new customs union deal with the EU. A customs union is where countries agree not to impose tariffs on each others' goods and have a common tariff on goods coming in from elsewhere. The UK is currently part of the EU customs union but that stops the UK being able to do its own trade deals with other countries. Reality Check: How could customs union work?
What do 'soft' and 'hard' Brexit mean?
These terms have increasingly been used as debate focused on the terms of the UK's departure from the EU. There is no strict definition of either, but they are used to refer to the closeness of the UK's relationship with the EU post-Brexit.
So at one extreme, "hard" Brexit could involve the UK refusing to compromise on issues like the free movement of people even if meant leaving the single market. At the other end of the scale, a "soft" Brexit might follow a similar path to Norway, which is a member of the single market and has to accept the free movement of people as a result of that.
What happens if there is no deal with the EU?
Prime Minister Theresa May says leaving the EU with no deal whatsoever would be better than signing the UK up to a bad one. Without an agreement on trade, the UK would have to operate under World Trade Organisation rules, which could mean customs checks and tariffs.
Labour says the idea of walking away with no deal must not be an option, and it would give MPs a say on the final Brexit deal - but it has ruled out a second referendum on the terms of that deal.
Some argue leaving the single market would make little difference because the UK's trading partners in the EU would not want to start a trade war. Others say it will mean greater costs for UK businesses buying and selling goods abroad.
There are also questions about what would happen to Britain's position as global financial centre, without access to the single market, and the land border between the UK and Ireland. There is also concern that Brits living abroad in the EU could lose residency rights and access to free emergency health care. Here is a full explanation of what 'no deal' could mean
What happens to EU citizens living in the UK?
The Conservatives has declined to give a firm guarantee about the status of EU nationals currently living in the UK, saying this is not possible without a reciprocal pledge from other EU members about the millions of British nationals living on the continent.
Labour has said it would guarantee the rights of of EU citizens living in the UK to stay there on "day one" of a Labour government.
Whatever happens in the general election, EU nationals with a right to permanent residence, which is granted after they have lived in the UK for five years, should not see their rights affected.
What happens to UK citizens working in the EU?
A lot depends on the kind of deal the UK agrees with the EU. If the government opted to impose work permit restrictions on EU nationals, then other countries could reciprocate, meaning Britons would have to apply for visas to work.
What about EU nationals who want to work in the UK?
Again, it depends on whether the UK government decides to introduce a work permit system of the kind that currently applies to non-EU citizens, limiting entry to skilled workers in professions where there are shortages. Citizens' Advice has reminded people their rights have not changed yet and asked anyone to contact them if they think they have been discriminated against following the Leave vote.
What does the fall in the value of the pound mean for prices in the shops?
People travelling overseas from the UK have found their pounds are buying fewer euros or dollars after the Brexit vote. The day-to-day spending impact is likely to be more significant. Even if the pound regains some of its value, currency experts expect it to remain at least 10% below where it was on 23 June, in the long term.
This means imported goods will consequently get more expensive - some price rises for food, clothing and homeware goods have already been seen and the issue was most notably illustrated by the dispute between Tesco and Marmite's makers about whether prices would be put up or not in the stores.
The latest UK inflation figures, for April, showed the CPIH inflation rate rising to 2.6%, its highest level for three and a half years, with signs of more cost pressures set to feed through in the months to come.
Will immigration be cut?
Prime Minister Theresa May has said one of the main messages she has taken from the Leave vote is that the British people want to see a reduction in immigration. She has said this will be a focus of Brexit negotiations as she remains committed to getting net migration - the difference between the numbers entering and leaving the country - down to a "sustainable" level, which she defines as being below 100,000 a year.
Labour has said the free movement of people has to end when Britain leaves the EU. It has yet to reveal what system it would use for people who come to the UK for work or study.
Net migration to the UK was estimated to be 248,000 in 2016 - a fall of 84,000 from 2015. The total number of people moving to the UK was made up of 264,000 non-EU citizens, 250,000 EU citizens and 74,000 British citizens. Balancing that 117,000 EU citizens left the UK, out of an estimated total of 339,000 emigrants.
Could there be a second referendum?
It seems highly unlikely. Both the Conservatives and the Labour Party have ruled out another referendum, arguing that it would be an undemocratic breach of trust with the British people who clearly voted to Leave.
Will MPs get a vote on the Brexit deal?
Yes. Theresa May has appeared keen to avoid a vote on her negotiating stance, to avoid having to give away her priorities, but she has promised there will be a Commons and Lords vote to approve whatever deal the UK and the rest of the EU agree at the end of the two year process.
Labour is also promising a vote in Parliament, but unlike the Conservatives they want to give MPs and peers the power to send the UK back to the negotiating table if they don't like the terms of the deal. The Conservative vote would be on a "take it or leave it basis".
It is worth mentioning that any deal also has to be agreed by the European Parliament - with British MEPs getting a chance to vote on it there.
Will I need a visa to travel to the EU?
While there could be limitations on British nationals' ability to live and work in EU countries, it seems unlikely they would want to deter tourists. There are many countries outside the European Economic Area, which includes the 28 EU nations plus Iceland, Lichtenstein and Norway, that British citizens can visit for up to 90 days without needing a visa and it is possible that such arrangements could be negotiated with European countries.
Will I still be able to use my passport?
Yes. It is a British document - there is no such thing as an EU passport, so your passport will stay the same. In theory, the government could, if it wanted, decide to change the colour, which is currently standardised for EU countries, says the BBC's Europe correspondent, Chris Morris.
Some say we could still remain in the single market - but what is a single market?
The single market is seen by its advocates as the EU's biggest achievement and one of the main reasons it was set up in the first place. Britain was a member of a free trade area in Europe before it joined what was then known as the common market. In a free trade area countries can trade with each other without paying tariffs - but it is not a single market because the member states do not have to merge their economies together.
The European Union single market, which was completed in 1992, allows the free movement of goods, services, money and people within the European Union, as if it was a single country. It is possible to set up a business or take a job anywhere within it. The idea was to boost trade, create jobs and lower prices. But it requires common law-making to ensure products are made to the same technical standards and imposes other rules to ensure a "level playing field".
Critics say it generates too many petty regulations and robs members of control over their own affairs. Mass migration from poorer to richer countries has also raised questions about the free movement rule. Theresa May has ruled out the UK staying in the single market. Labour leader Jeremy Corbyn has said continued membership of the single has to be an option in negotiations with Brussels. Read more: A free trade area v EU single market
Has any other member state ever left the EU?
No nation state has ever left the EU. But Greenland, one of Denmark's overseas territories, held a referendum in 1982, after gaining a greater degree of self government, and voted by 52% to 48% to leave, which it duly did after a period of negotiation. The BBC's Carolyn Quinn visited Greenland to find out how they did it.
What does this mean for Scotland?
Scotland's First Minister Nicola Sturgeon said in the wake of the Leave result that it was "democratically unacceptable" that Scotland faced being taken out of the EU when it voted to Remain. She said Theresa May's decision to rule out the UK staying in the single market meant Scotland should have a choice between a "hard Brexit" and becoming an independent country, possibly in the EU. Ms Sturgeon has officially asked for permission for a second referendum to be held, saying that she wanted the vote to be held between the autumn of 2018 and spring 2019. Theresa May has said "this is not the time" for a second referendum.
What does it mean for Northern Ireland?
The land border between Northern Ireland and EU member the Republic of Ireland is likely to be a key part of the Brexit talks. There is currently a common travel area between the UK and the Republic.
Like Scotland, Northern Ireland voted to remain in the EU in last year's referendum. The result in Northern Ireland was 56% for Remain and 44% for Leave.
Sinn Fein, which was part of the ruling coalition in the Northern Ireland Assembly before it was suspended, has called for a referendum on leaving the UK and joining the Republic of Ireland as soon as possible.
The Conservatives have rejected Sinn Fein's call, saying there was no evidence opinion had shifted in favour of a united Ireland.
But Conservative Brexit spokesman David Davis has said that should the people of Northern Ireland ever vote to leave the UK, they would "be in a position of becoming part of an existing EU member state, rather than seeking to join the EU as a new independent state".
It would then be up to the EU Commission "to respond to any specific questions about the procedural requirements for that to happen," he added.
But Mr Davis said the UK government's "clear position is to support Northern Ireland's current constitutional status: as part of the UK, but with strong links to Ireland".
Labour leader Jeremy Corbyn says there should be a referendum on Irish unity if the Northern Ireland Assembly wants one.
The issue has been further complicated by Theresa May's deal with the Democratic Unionist Party, enabling her to form a minority government, which some critics, including former Tory Prime Minister Sir John Major, have warned could adversely effect the peace process and mean the UK government would no longer be seen as an "impartial honest broker" in restoring the power-sharing arrangements and upholding Northern Irish institutions.
How will pensions, savings, investments and mortgages be affected?
During the referendum campaign, David Cameron said the so-called "triple lock" for state pensions would be threatened by a UK exit. This is the agreement by which pensions increase by at least the level of earnings, inflation or 2.5% every year - whichever is the highest.
Theresa May duly ditched the commitment to the triple lock in the party's election manifesto, replacing it from 2020 with a "double lock", which would see pensions rise by at least the level of earnings or inflation, but not by a guaranteed minimum of 2.5%.
Labour had pledged to keep the triple lock.
So far there has been a cut in interest rates, which has helped keep mortgage and other borrowing rates low. There are yet to be signs that rising inflation have worried the Bank of England enough to consider raising interest rates. But if that happened it would make mortgages and loans more expensive to repay - but would be good news for savers.
Will duty-free sales on Europe journeys return?
Journalists and writers on social media have greeted the reintroduction of duty-free sales as an "upside" or "silver lining" of Brexit. As with most Brexit consequences, whether this will happen depends on how negotiations with the EU play out - whether the "customs union" agreement between Britain and the EU is ended or continued.
Will EHIC cards still be valid?
They are at the moment but no-one knows the longer term prospects for definite. The EHIC card - which entitles travellers to state-provided medical help for any condition or injury that requires urgent treatment, in any other country within the EU, as well as several non-EU countries - is not an EU initiative. It was negotiated between countries within a group known as the European Economic Area, often simply referred to as the single market (plus Switzerland, which confusingly is not a member of the EEA, but has agreed access to the single market). Therefore, the future of Britons' EHIC cover could depend on whether the UK decided to sever ties with the EEA.
Will cars need new number plates?
Probably not, says BBC Europe correspondent Chris Morris, because there's no EU-wide law on vehicle registration or car number places, and the EU flag symbol is a voluntary identifier and not compulsory. The DVLA says there has been no discussion about what would happen to plates with the flag if the UK voted to leave.
Could MPs block an EU exit?
Could the necessary legislation pass the Commons, given that a lot of MPs in the current Parliament - all SNP and Lib Dems, nearly all Labour and many Conservatives - were in favour of staying? The referendum result is not legally binding - Parliament still has to pass the laws that will get Britain out of the 28 nation bloc, starting with the repeal of the 1972 European Communities Act.
The withdrawal agreement also has to be ratified by Parliament - the House of Lords and/or the Commons could vote against ratification, according to a House of Commons library report.
Will leaving the EU mean we don't have to abide by the European Court of Human Rights?
The European Court of Human Rights (ECHR) in Strasbourg is not a European Union institution. It was set up by the Council of Europe, which has 47 members including Russia and Ukraine. So quitting the EU will not exempt the UK from its decisions.
The Conservatives are committed to repealing the Human Rights Act which requires UK courts to treat the ECHR as setting legal precedents for the UK, in favour of a British Bill of Rights. As part of that, a Conservative government would be expected to announce measures that will boost the powers of courts in England and Wales to over-rule judgements handed down by the ECHR.
The Labour Party, the Liberal Democrats and the Green Party have all campaigned against Conservative proposals to repeal the Human Rights Act.
The EU also has its own European Court of Justice, whose decisions are binding on EU institutions and member states. Its rulings have sometimes caused controversy in Britain and supporters of a Brexit have called for immediate legislation to curb its powers.
Will the UK be able to rejoin the EU in the future?
BBC Europe editor Katya Adler says the UK would have to start from scratch with no rebate, and enter accession talks with the EU. Every member state would have to agree to the UK re-joining. But she says with elections looming elsewhere in Europe, other leaders might not be generous towards any UK demands. New members are required to adopt the euro as their currency, once they meet the relevant criteria, although the UK could try to negotiate an opt-out.
Who wanted the UK to leave the EU?
The UK Independence Party, which received nearly four million votes - 13% of those cast - in the 2015 general election, but who saw their vote collapse to about a quarter of that at this year's election, has campaigned for many years for Britain's exit from the EU. They were joined in their call during the referendum campaign by about half the Conservative Party's MPs, including Boris Johnson and five members of the then Cabinet. A handful of Labour MPs and Northern Ireland party the DUP were also in favour of leaving.
What were their reasons for wanting the UK to leave?
They said Britain was being held back by the EU, which they said imposed too many rules on business and charged billions of pounds a year in membership fees for little in return. They also wanted the UK to make all of its own laws again, rather than being created through shared decision making with other EU nations.
Immigration was also a big issue for Brexit supporters, They wanted Britain to take back full control of its borders and reduce the number of people coming here to live and/or work.
One of the main principles of EU membership is "free movement", which means you don't need to get a visa to go and live in another EU country. The Leave campaign also objected to the idea of "ever closer union" between EU member states and what they see as moves towards the creation of a "United States of Europe".
Who wanted the UK to stay in the EU?
Then Prime Minister David Cameron was the leading voice in the Remain campaign, after reaching an agreement with other European Union leaders that would have changed the terms of Britain's membership had the country voted to stay in.
He said the deal would give Britain "special" status and help sort out some of the things British people said they didn't like about the EU, like high levels of immigration - but critics said the deal would make little difference.
Sixteen members of Mr Cameron's Cabinet, including the woman who would replace him as PM, Theresa May, also backed staying in. The Conservative Party was split on the issue and officially remained neutral in the campaign. The Labour Party, Scottish National Party, Plaid Cymru, the Green Party and the Liberal Democrats were all in favour of staying in.
The then US president Barack Obama also wanted Britain to remain in the EU, as did the leaders of other EU nations such as France and Germany.
What were their reasons for wanting the UK to stay?
Those campaigning for Britain to stay in the EU said it got a big boost from membership - it makes selling things to other EU countries easier and, they argued, the flow of immigrants, most of whom are young and keen to work, fuels economic growth and helps pay for public services.
They also said Britain's status in the world would be damaged by leaving and that we are more secure as part of the 28 nation club, rather than going it alone.
What about businesses?
Big business - with a few exceptions - tended to be in favour of Britain staying in the EU because it makes it easier for them to move money, people and products around the world.
Given the crucial role of London as a financial centre, there's interest in how many jobs may be lost to other hubs in the EU. Four of the biggest US banks have committed to helping maintain the City's position. But HSBC will move up to 1,000 jobs to Paris, the BBC understands.
Some UK exporters say they've had increased orders or enquiries because of the fall in the value of the pound. Others are less optimistic, fearing products for the European market may have to be made at plants in the EU.
Who led the rival sides in the campaign?
- Britain Stronger in Europe - the main cross-party group campaigning for Britain to remain in the EU was headed by former Marks and Spencer chairman Lord Rose. It was backed by key figures from the Conservative Party, including Prime Minister David Cameron and Chancellor George Osborne, most Labour MPs, including party leader Jeremy Corbyn and Alan Johnson, who ran the Labour In for Britain campaign, the Lib Dems, Plaid Cymru, the Alliance party and the SDLP in Northern Ireland, and the Green Party. Who funded the campaign: Britain Stronger in Europe raised £6.88m, boosted by two donations totalling £2.3m from the supermarket magnate and Labour peer Lord Sainsbury. Other prominent Remain donors included hedge fund manager David Harding (£750,000), businessman and Travelex founder Lloyd Dorfman (£500,000) and the Tower Limited Partnership (£500,000). Read a Who's Who guide. Who else campaigned to remain: The SNP ran its own remain campaign in Scotland as it did not want to share a platform with the Conservatives. Several smaller groups also registered to campaign.
- Vote Leave - A cross-party campaign that has the backing of senior Conservatives such as Michael Gove and Boris Johnson plus a handful of Labour MPs, including Gisela Stuart and Graham Stringer, and UKIP's Douglas Carswell and Suzanne Evans, and the DUP in Northern Ireland. Former Tory chancellor Lord Lawson and SDP founder Lord Owen were also involved. It had a string of affiliated groups such as Farmers for Britain, Muslims for Britain and Out and Proud, a gay anti-EU group, aimed at building support in different communities. Who funded the campaign: Vote Leave raised £2.78m. Its largest supporter was businessman Patrick Barbour, who gave £500,000. Former Conservative Party treasurer Peter Cruddas gave a £350,000 donation and construction mogul Terence Adams handed over £300,000. Read a Who's Who guide. Who else campaigned to leave: UKIP leader Nigel Farage is not part of Vote Leave. His party ran its own campaign. The Trade Union and Socialist Coalition is also running its own out campaign. Several smaller groups also registered to campaign.
Will the EU still use English?
Yes, says BBC Europe editor Katya Adler. There will still be 27 other EU states in the bloc, and others wanting to join in the future, and the common language tends to be English - "much to France's chagrin", she says.
Will Brexit harm product safety?
Probably not, is the answer. It would depend on whether or not the UK decided to get rid of current safety standards. Even if that happened any company wanting to export to the EU would have to comply with its safety rules, and it's hard to imagine a company would want to produce two batches of the same products.
Here are a selection of questions sent in - you can ask yours via the form at the end of this page
Which MPs were for staying and which for leaving?
The good news for Edward, from Cambridge, who asked this question, is we have been working on exactly such a list. Click here for the latest version.
How much does the UK contribute to the EU and how much do we get in return?
In answer to this query from Nancy from Hornchurch - the UK is one of 10 member states who pay more into the EU budget than they get out, only France and Germany contribute more. In 2014/15, Poland was the largest beneficiary, followed by Hungary and Greece.
The UK also gets an annual rebate that was negotiated by Margaret Thatcher and money back, in the form of regional development grants and payments to farmers, which added up to £4.6bn in 2014/15. According to the latest Treasury figures, the UK's net contribution for 2014/15 was £8.8bn - nearly double what it was in 2009/10.
The National Audit Office, using a different formula which takes into account EU money paid directly to private sector companies and universities to fund research, and measured over the EU's financial year, shows the UK's net contribution for 2014 was £5.7bn. Read more number crunching from Reality Check.
If I retire to Spain or another EU country will my healthcare costs still be covered?
David, from East Sussex, is worried about what will happen to his retirement plans. This is one of those issues where it is not possible to say definitively what would happen. At the moment, the large British expat community in Spain gets free access to Spanish GPs and their hospital treatment is paid for by the NHS. After they become permanent residents Spain pays for their hospital treatment.
In some other EU countries such as France expats of working age are expected to pay the same healthcare costs as locals but once they reach retirement age their medical bills are paid by the NHS.
If Britain remains in the single market, or the European Economic Area as it is known, it might be able to continue with this arrangement, according to a House of Commons library research note. If Britain has to negotiate trade deals with individual member states, it may opt to continue paying for expats' healthcare through the NHS or decide that they would have to cover their own costs if they continue to live abroad, if the country where they live declines to do so.
What will happen to protected species?
Dee, from Launceston, wanted to know what would happen to EU laws covering protected species such as bats in the event of Britain leaving the EU. The answer is that they would remain in place, initially at least. After the Leave vote, the government will probably review all EU-derived laws in the two years leading up to the official exit date to see which ones to keep or scrap.
The status of Special Areas of Conservation and Special Protection Areas, which are designated by the EU, would be reviewed to see what alternative protections could be applied. The same process would apply to European Protected Species legislation, which relate to bats and their habitats.
The government would want to avoid a legislative vacuum caused by the repeal of EU laws before new UK laws are in place - it would also continue to abide by other international agreements covering environmental protection.
How much money will the UK save through changes to migrant child benefits and welfare payments?
Martin, from Poole, in Dorset, wanted to know what taxpayers would have got back from the benefit curbs negotiated by David Cameron in Brussels. We don't exactly know because the details were never worked out. HM Revenue and Customs suggested about 20,000 EU nationals receive child benefit payments in respect of 34,000 children in their country of origin at an estimated cost of about £30m.
But the total saving would have been significantly less than that because Mr Cameron did not get the blanket ban he wanted. Instead, payments would have been linked to the cost of living in the countries where the children live. David Cameron said as many as 40% of EU migrant families who come to Britain could lose an average of £6,000 a year of in-work benefits when his "emergency brake" was applied. The DWP estimated between 128,700 and 155,100 people would be affected. But the cuts would have been phased in. New arrivals would not have got tax credits and other in-work benefits straight away but would have gradually gained access to them over a four year period at a rate that had not been decided. The plan will never be implemented now.
Will we be barred from the Eurovision Song Contest?
Sophie from Peterborough, who asks the question, need not worry. We have consulted Alasdair Rendall, president of the UK Eurovision fan club, who says: "All participating countries must be a member of the European Broadcasting Union. The EBU - which is totally independent of the EU - includes countries both inside and outside of the EU, and also includes countries such as Israel that are outside of Europe. Indeed the UK started participating in the Eurovision Song Contest in 1957, 16 years before joining the then EEC."
Has Brexit made house prices fall?
So far, the answer is no. But there has been anecdotal evidence of house prices falling at the top of the market in Central London and the annual increase in the price of property has fallen from 9.4% at the time of the referendum to 7.2% in December.
What is the 'red tape' that opponents of the EU complain about?
Ged, from Liverpool, suspects "red tape" is a euphemism for employment rights and environmental protection. According to the Open Europe think tank, four of the top five most costly EU regulations are either employment or environment-related. The UK renewable energy strategy, which the think-tank says costs £4.7bn a year, tops the list. The working time directive (£4.2bn a year) - which limits the working week to 48 hours - and the temporary agency workers directive (£2.1bn a year), giving temporary staff many of the same rights as permanent ones - are also on the list.
There is nothing to stop a future UK government reproducing these regulations in British law following the decision to leave the EU. And the costs of so-called "red tape" will not necessarily disappear overnight - if Britain opted to follow the "Norway model" and remained in the European Economic Area most of the EU-derived laws would remain in place.
Will Britain be party to the Transatlantic Trade and Investment Partnership?
Ste, in Bolton, asked about this. The Transatlantic Trade and Investment Partnership - or TTIP - currently under negotiation between the EU and United States would create the biggest free trade area the world has ever seen.
Cheerleaders for TTIP, including former PM David Cameron, believed it could make American imports cheaper and boost British exports to the US to the tune of £10bn a year.
But many on the left, including Labour leader Jeremy Corbyn, fear it will shift more power to multinational corporations, undermine public services, wreck food standards and threaten basic rights.
New US President Donald Trump is not a fan of the TTIP agreement, which means it is now seen as unlikely to be agreed - but whatever happens, when the UK quits the EU it will not be part of TTIP and will have to negotiate its own trade deal with the US.
What impact will leaving the EU have on the NHS?
Paddy, from Widnes, wanted to know how leaving the EU will affect the number of doctors we have and impact the NHS.
This became an issue in the referendum debate after the Leave campaign claimed the money Britain sends to the EU, which it claimed was £350m a week, could be spent on the NHS instead. The BBC's Reality Check team looked into this claim.
Before the vote Health Secretary Jeremy Hunt warned that leaving the EU would lead to budget cuts and an exodus of overseas doctors and nurses. The Leave campaign dismissed his intervention as "scaremongering" and insisted that EU membership fees could be spent on domestic services like the NHS.
Since the referendum spending on the NHS has continued at the same level as planned. EU citizens working for the NHS are expected to get the right to stay in the UK, although details on EU citizens in the UK and UK citizens elsewhere in the EU are yet to be finalised (see earlier answer).
Sally Miller bought a house in Spain nine years ago and plans to retire there in the next five years. She asks how Brexit will affect this.
The BBC's Kevin Connolly says:
The issue of free movement - the rights of EU citizens to live and work in the UK - was a huge issue in the Brexit referendum of course, and will be a big part of the exit negotiations.
We've heard quite a bit from the British side already with the government saying that securing the status and rights of EU nationals in the UK and UK nationals in the EU is one of the government's earliest priorities, and specifically that it is looking for a reciprocal deal.
So you might feel the mood music is encouraging but all we can say for sure is that, while there are no guarantees yet, it will be a big part of the Brexit negotiations to come.
Jonathan Eaton is a Briton living in the Netherlands with his wife, who is Dutch. He asks what rights to benefits and housing he will have if he has to return to the UK.
BBC assistant political editor Norman Smith says:
The short answer is there is no easy access to benefits. As it stands at the moment, Brexit aside, you will have to pass what's known as a habitual residence test which was introduced in 1994 and applies to British citizens just as EU citizens.
The rules have been tightened up which means for some benefits, if you have been out of the country you can't even think about applying for the test for several months. For example, when it comes to job seeker's allowance, you cannot even take the test to apply for those benefits for three months. And that was done to stop EU citizens coming here and just getting on benefits straight away.
After three months, you can take the test which looks at your English language skills, what sort of efforts you made to find work before coming to the UK. It also considers how strong a tie you have to the UK, whether you have property or family here and what your intentions are in terms of staying and working, or returning.
But once you have taken the test, if you pass it then you should be eligible to apply for a range of benefits, as long as you meet the usual requirements in terms of income and showing you are looking for work. That is likely to continue when we move fully on to Universal Credit.
The one sort of unknown in the whole system is what happens with Brexit negotiations, in terms of guaranteeing the rights of British nationals abroad.
And we simply don't know what that will involve and whether in any way that might impact on how soon you can apply for benefits when you come back to Britain.
What will happen to the European Health Insurance Card when Britain leaves the EU, asks Terry Hunt.
Norman Smith says:
At the moment, we can be sure that if we feel a little bit peaky in another part of the EU then we're pretty much OK because we can get the same sort of healthcare as citizens already in that country.
That applies to prescriptions, GP visits and hospitals stays. What happens when we leave the EU is, like so much of Brexit-land, unknown. The current system could continue.
If, however, that were not possible, we could still have deals with individual countries about reciprocal health rights, because we already have that with a number of countries such as Australia, Israel, and Russia. But there are no guarantees we will be able to arrive at these reciprocal deals.
So my guess is that it will be in everyone's interest just to carry on with the current coverage. But failing that, my advice would be to keep taking the vitamins, pack some Lemsip and stay away from draughty windows when you're travelling abroad.
Will I have to buy a new passport and driving licence, and will my rights to use them freely across Europe be taken away from me after Brexit, asks Francis Lee.
Kevin Connolly says:
At the moment UK passports carry the words European Union and British driving licences have the blue square with yellow flags of the EU. That will presumably change after Brexit but it seems likely that the change will be phased in so that you'll simply get documents with the new design when the old ones expire. That's what happened, I seem to remember, when the UK joined the EU. Anything else would be expensive and risk flooding the system, after all.
The right to use them freely is an interesting question. When we talk about restrictions on freedom of movement we generally mean the freedom to live and work in another country. If Britain poses restrictions on the EU in that respect then it can expect some kind of response.
But in terms of tourism there are plenty of non-EU countries whose citizens can visit the UK for up to 90 days without a visa. And, as part of the Brexit negotiations, you'd expect similar arrangements to be discussed for the UK.
Both sides need each others' tourists and, after all, if you can drive a car in the United States on a UK licence then it doesn't seem fanciful to assume that you'll be able to do the same in Europe in future.
It is very clear that the PM and the government want to leave the tyranny of the European Court of Justice. Why has leaving the European Court of Human Rights (an organisation far more hated than the ECJ) been ignored, asks Barry Fryer.
Kevin Connolly says:
Two different courts here of course, so two different bits of politics. Crucially, the European Court of Human Rights is not an EU institution and that's why discussions about leaving it have not formed a key part of the Brexit debate.
The European Court of Justice - the ECJ - is one of the primary institutions of the European Union and administers EU law. So, while it might have a role in supervising a future trade deal, part of the goal of Brexit was to remove the UK from the ECJ's jurisdiction.
The European Court of Human Rights which, as Barry points out, can be even more controversial, is a body set up not by the EU but by member states of the Council of Europe, a separate institution which contains countries that aren't EU members.
It's this court which has produced rulings which have been controversial in the UK, including blocking the extradition of Abu Qatada and establishing the right of serving prisoners to vote in elections - and leaving the EU won't change anything here.
Adrian Wallis runs a small electronics company and wants to know about export tariffs after Brexit, and what they'd mean for his business.
Kevin Connolly says:
As long as Britain has been in the EU we haven't really talked much about tariffs. That's because all trade within the European Economic Area is tariff-free. On top of that the EU has trade agreements with 52 other countries as well.
After Brexit, Britain is going to have to negotiate new deals all on its own. That's both a problem and an opportunity.
For example you can use tariffs against foreign imports to protect businesses you care about, as the EU does with agricultural produce, but you do then run the risk of retaliation from your trading partners.
The key body in all of this is the World Trade Organisation and at the moment the UK is only a member via its membership of the EU.
One bit of good news is that the UK will automatically become a member in its own right as soon as it leaves the EU.
That matters because in the period when the UK is negotiating a new trade deal with the EU, and that could take years, trade would be conducted under WTO rules.
At the moment, for non-food items, that implies an average tariff of about 2.3%
But suppose the EU were to impose a 10% tariff on UK car imports, for example. Well, then the UK could impose the same tariff on German and French cars.
In theory, an economist would say that creates a situation where everyone has an incentive to sort out a better deal for their consumers.
The snag is that these things take years, if not decades. They tend to be done on a country-by-country and sector-by-sector basis.
So if Adrian is waiting to find out the implications for his business, then I'm afraid he's going to have to be patient.
Maybe very, very patient.
What impact will leaving the European Union have on the UK's long term political influence in Europe, asks Peter Hoare.
Norman Smith says:
There are basically two views on what will happen in terms of clout when outside the EU.
View one is that the UK projects power and influence in the world, working through organisations such as the EU and that on our own it'll be a much diminished force.
View two is that unencumbered by the other 27 members, the UK can get on with things and start adopting a much more independent, self-confident, assertive role on the world stage.
My take is that not much is probably going to change.
I say that because the UK'll still be a member of significant organisations such as the UN and Nato, and will still be co-operating with EU partners. For example, there will still be close ties on defence with the French.
The UK will still be the same old Britain, will still have significant military force, will still be a wealthy country and will still be a nuclear power, so I don't think people will suddenly think the UK's an entirely different country.
Are other countries likely to leave the EU and if so could we start a new free trade area, asks David John.
Kevin Connolly says:
Funnily enough, I was discussing this question just the other day with a French politician, a conservative and a real Europhile, and he said he thought if there was a free vote in France tomorrow, as the right wing National Front would like, that the French would vote to leave.
But generally speaking I can't see much prospect of a tidal wave of insurrectionist, exitism sweeping the continent. When a country like Ireland has a spat with the EU about tax, for example, it does annoy Irish politicians, but most mainstream leaders in the Europe have grown up with the idea that the EU has brought peace and prosperity for decades.
Lots of them see plenty that irritates them about the European Union, but they mainly argue that the benefits hugely outweigh the irritations. And in countries where you do find euroscepticism, such as Poland and Hungary, there is also a healthy awareness that there are huge financial benefits to membership.
As for the future, we will see. If the UK were to get a fantastic Brexit deal then maybe others would be tempted to go.
But the truth is, lots of European politicians want the EU to be tough with Britain precisely to stop other countries from following it through the door.
As to Britain forming its own free trade area, I think it seems an awfully long shot and on balance it is unlikely, not least because there are not that many free countries around available to recruit into another free trade area.
Britain could perhaps join the Free Trade Association along with Norway, Lichtenstein and Switzerland. But of course it would be joining under existing rules, so the likeliest future for a post-Brexit UK, I think, is a future where it tries to do the best deal possible with the EU and then looks around for other free trade deals.
But that would fall short of creating a free trade area based on the UK itself.
What will happen to the borders in Gibraltar and Northern Ireland, asks Nigel May.
Kevin Connolly says:
I think the question of what is going to happen to difficult borders after Brexit is one of the most difficult of the lot.
Since 1985 when Spain joined the EU, it has basically been prevented from closing the border with Gibraltar as a way of applying pressure to the British territory.
In fact, 12,000 Spanish people cross into the territory to work every day and the area of Spain around Gibraltar is a pretty depressed area so they are important jobs.
On the other hand, the Spanish have talked openly about this being an opportunity to get Gibraltar back. Jose Manuel Garcia-Margallo, its minister of foreign affairs, said in September the UK's vote to leave the EU was "a unique historical opportunity in more than three hundred years to get Gibraltar back".
But at a minimum, as things stand, it looks to me as though they could certainly re-impose border controls if they chose to.
The situation with Ireland's border is more complex.
For those of us for whom Northern Ireland is home, the total disappearance of military check points on the border is one of the most tangible daily reminders of the end of the troubles and no one wants a border like that back.
But, when the day comes when Ireland is in the EU and the UK is not, then the Irish border of course is also going to be the UK's land border with the European Union.
Conservative leader Theresa May has said we don't see a return to the borders of the past, but the reality is that if Britain leaves the common customs area, then presumably some sort of checks are going to be necessary on that border.
And if the UK wants to stop Polish or Romanian migrant workers using Dublin airport as a back door into the UK, then it is going to have to do something about that too.
Of course, what it will all mean for towns and villages like Belleek and Belcoo in County Fermanagh, which more or less straddle the border, is hard to imagine.
How much has Brexit cost so far and how much will it cost by the end, asks Simon Johnston.
Norman Smith says:
I think the truth is, no one truly knows what the costs will be of leaving the EU.
That is in part because it is at the very centre of the whole row over Brexit, so if you talk to Brexiteers then they assume we will be "quids in" by leaving the EU, if you talk to Remainers then they assume it is going to be a catastrophe.
We simply don't know because we don't know what is going to happen to the economy, whether it is going to prosper or whether it is going to flounder.
How will access to healthcare change for expats living in the EU, asks Veronique Bradley, who lives in Italy.
Kevin Connolly says:
Healthcare is one of those issues that remains relatively simple as long as the UK remains in the EU.
It is just part of a range of citizens' rights that apply across the entire union. After Brexit, I suppose there will be two possibilities.
The first and easiest would be that the negotiators come up with a reciprocal deal that keeps the current arrangements, or something a bit like them, in place.
If they don't, the situation will depend on the individual country where you live.
For the Bradleys in Italy, for example, residents from non-EU countries, and that will soon include the Brits, will have to finalise their residency status, acquire an Italian identity card and then apply for an Italian health insurance card.
If they visit the UK at the moment, access to the NHS for non-resident Brits is not straightforward unless you have a European health insurance card.
The right to treatment is based on residency, not on your tax status.
So, even if you live abroad and pay some British tax on a buy-to-let property for instance, you might find yourself getting a bill for any NHS treatment you end up getting while you are back in the UK.
What will happen to EU nationals who lived and worked in the UK and now receive a British state pension, asks Peter Barz, a German citizen living in the UK.
Norman Smith says:
If you are an EU national and you get a British state pension, nothing much should change, because the state pension is dependent not on where you come from, but on how long you have paid National Insurance contributions in the UK.
So it doesn't matter whether you come from Lithuania or Latvia or Transylvania or Timbuktu, what counts is how much you have paid in terms of National Insurance contributions.
There is one wrinkle though and that is that you have to have paid in for at least 10 years.
Under the current rules, if you are an EU citizen and haven't paid in for 10 years, you can point to any contributions you have made in your native country and say, "I paid in there", and that will count.
That works for EU countries and another 16 countries with which the UK has social security agreements.
Once we have left the EU, you will no longer be able to do that unless we negotiate new reciprocal agreements.
If we don't then potentially, if you have paid in fewer than than 10 years' worth of National Insurance contributions, you will not get a British state pension.
Is it possible to be both an EU citizen and not an EU citizen, asks Declan O'Neill, who holds an Irish passport.
Kevin Connolly says:
I should probably declare some sort of interest here as a dual Irish and British national myself.
Of course, anyone born in Northern Ireland has an absolute right to carry both passports.
Declan might be happy to know that this is one of the few questions where I can't see a downside as long as you are happy and comfortable carrying both passports.
The Irish document means you continue to enjoy the benefits of EU citizenship, and the British passport will give you full rights in the UK at the same time.
Call it one of the clear joys of coming from Northern Ireland, alongside the rolling hills, rugged coastline and enjoyable breaks between the showers.
All you have to do is remember to carry the Irish passport when you are joining the EU citizens-only queue at the airport in future.
Is there a get-out clause for Article 50, asks Gillian Coates.
Norman Smith says:
I think the honest answer is you would have to be a legal eagle to answer this.
But my take on it is that legally it looks like once we trigger Article 50 we are locked in, and that is certainly how the European Parliament reads it.
And there is a view that if we were in this two-year process after triggering Article 50 and we wanted to get out of it, then ultimately that would be a decision for the European Court of Justice.
However, in the real world I think it is likely to be rather different, whatever the legal protocol.
I think the truth is, if we were trundling along and decided it was all going to be catastrophic and we have got to pull up the handbrake pretty sharpish, a lot of other EU countries would be probably be laughing at us, but I think at the same time they would probably be quite pleased we weren't going.
So I think the short answer is: legally, it doesn't look so good if you want to get out of it, but politically, it probably can be done with the support of other European leaders.
Eric Degerland asks when UK passports are going to change.
Kevin Connolly says:
This takes us to the heart of an issue that lots of people really care about. It will be a real and palpable sign of Brexit when there is a new UK passport without the words "European Union" on the front cover.
Sadly, the short answer is we don't really know when the change will come about.
But we can say that the cheapest thing for the government to do would be to phase in the new passports as people's old ones expire.
So if you're looking forward to getting back that blue hard-back passport we had in the old days, you may have a long time to wait.
But we can say that the cheapest thing for the government to do would be to phase in the new passports as people's old ones expire.
So if you're looking forward to getting back that blue hard-back passport we had in the old days, you may have a long time to wait.