Thousands more NHS patients and visitors will be able to access free hospital car parking, the government says.
From April, all 206 hospital trusts in England will be expected to begin offering the concession in line with the government's manifesto promise.
Those with the "greatest need" will benefit.
That includes groups such as people with disabilities and NHS staff working night shifts.
Currently, hourly charges at hospitals for parking vary between £1 and £4. It is up to trusts to make their own car parking arrangements.
NHS hospital car parking fees were abolished in Scotland and Wales in 2008, although a small number of hospitals in Scotland still charge as they remain tied in to contracts with private companies that manage their parking facilities. Fees may be charged in Northern Ireland.
Who will get free parking?
- Blue badge holders
- Frequent outpatients who have to attend regular appointments to manage long-term conditions
- Free parking will also be offered at specific times of the day to certain groups, including parents of sick children staying in hospital overnight and staff working night shifts
How much of a difference will it make?
The government says the change will make the NHS as accessible as possible for those who need it most and have little choice but to travel by car - without congesting car parks.
But it is not clear how many people will directly benefit.
Many hospitals already offer concessions - free or reduced charges or caps - for visitors that would fall into the "greatest need" category, as per existing guidelines.
The guidelines also recommend that any charges are "reasonable for the area" to keep fees in check, while deterring people, such as commuters, who do not have legitimate reasons for parking.
The government says many hospitals have ignored the guidance issued in 2015 and are charging the protected groups.
About 15% of NHS sites currently charge for disabled parking, according to NHS figures published in October.
For example, Royal Surrey County Hospital in Guildford charges blue badge holders £4 a day for parking, while Pinderfields, Pontefract and Dewsbury and District Hospitals in Yorkshire charge up to £2.80 day for blue badge holders.
Might hospitals lose out?
The government has said that no NHS trust will be left with less money because of the change.
Last year, hospital trusts in England made more than £254m from car parking charges, and a further £1.5m from parking fines, according to data from Freedom of Information requests.
The Conservative Party has said £78m per year will be provided, which it says is new funding for extra parking capacity, or compensation for lost fees.
The Patients Association says hospital parking should be free, calling the fees "a charge on people who are unwell".
The British Parking Association supports concessions for vulnerable groups, but does not believe that all hospital car parking should be free.
NHS Providers, which represents health managers, has also defended parking charges, saying fees can be used to ensure parking facilities are maintained, lit well, and secure, with any surplus reinvested back into wider services for patients.
Health Secretary Matt Hancock said: "We are today delivering on our manifesto commitment and setting out our new approach to NHS hospital parking charges."