When Pamela Juliano makes plans with her husband of 31 years, they have to compare schedules, just like any other dual-career couple. But unlike other couples, they have to decide whose house they’ll stay in for the weekend.

“We live about 125 miles apart,” said Juliano, 52, who lives in Utah in the US and is a government affairs and small business consultant. “We work during the week in different areas, and we strategise on how to spend our free time together.”

The pair have maintained two households for four years, ever since Juliano’s previous job as a congressional staffer was relocated. She needed to move to Salt Lake City for her career — and her husband Joe needed to stay in Helper, also in Utah, for his. “The decision was, ‘Look, this is what makes the most sense for us financially, and for our career goals’,” she said. “But it’s a partnership. I couldn’t do what I do, and Joe couldn’t do what he does, without each other.”

Committed couples who live in different places are officially deemed by sociologists to be Living Apart Together, or LAT. And depending on your definition of a couple, this moniker might apply to more people than you’d expect.

“Over a fifth of people in the UK who are normally classified as single are actually in a relationship but not living with their partner,” said Sasha Roseneil, professor of sociology at Birkbeck, University of London, and who has researched this particular population. “This is around 5 million people, or 9% of the adult population.”

About one-third of these people expressed a preference for not living together because they wanted to keep their own homes or were prioritising other responsibilities. And about 10% were in LAT relationships because their partner had a job or was studying elsewhere.

“For a relatively small number of career-minded women and men, living apart together relationships are proving to be unavoidable, particularly in professions where it is hard for couples to get jobs in the same city,” Roseneil said.

In Australia, 7% to 9% of the adult population has a partner who lives elsewhere, according to research by the Australian Institute of Family Studies. In the US, 3.6 million married adults live apart from their partners, according to the US Census Bureau. In Canada, 7% of adults are in a stable relationship but don’t share an address, according to Statistics Canada.

“For many, this arrangement gives the flexibility to meet the demands of contemporary life, and balance intimacy and independence,” said Miranda Phillips, research director for NatCen Social Research in the UK. Here’s what you should expect if you find yourself entering the same situation.

What it will take: You’ll have to be independent and trusting, with good communication skills, a budget for travel and the mental fortitude to be on your own. “If you need that physical presence of your partner on a daily basis, then it’s not going to be right for you,” said Bela Gandhi, founder and CEO of the Smart Dating Academy in the US.

How long you need to prepare: Make time in advance to discuss how the get-togethers will work (who will visit whom, and how often?) and how you will handle the expenses of two households. If there are relationship or other issues you need to work out beforehand, allot time for it.

“Be honest and realistic about the strong points in your marriage,” Juliano said. “In our case, we needed to communicate better. We made a commitment for quite a few months, as we knew we were going to be working up to this, that we would work on strategies that would improve our communication.”

Do it now: Have “the talk”. Make sure everyone is on the same page and that you know where you stand. “You should have total clarity on what I call ‘the state of your union’,” Gandhi said. “If you’re exclusive, you should be able to say, ‘This is my boyfriend’, meaning we are not seeing other people, or you have an open dating policy when you’re apart.”

Make a communication plan. Not everyone likes to be in touch the same way. You might like to send texts every hour and your significant other might like to catch up via phone at the end of the day. “Whatever you need in a relationship, be clear with your partner, and if you don’t have the same needs maybe you can meet halfway,” Gandhi said.

See each other regularly. “Regular contact is important to maintaining intimacy when living apart together, whether face-to-face or using other methods like phone or email,” Phillips said. Physical visits help keep the flame alive, but modern technology makes it possible to see each other’s faces daily. Take advantage of FaceTime, Skype and apps like WhatsApp to video chat.

Share the costs. “The biggest burden is the cost of transportation, and both partners should be in a position to understand and participate in this,” Gandhi said. This can be problematic if one partner is significantly wealthier than the other one, so set expectations up front. “No one wants to feel taken advantage of or powerless in the relationship,” Gandhi said.

Be on top of budgeting. Running two households means dealing with two sets of bills and a more complicated budget. “If you’re in a marriage where you don’t talk about finances until it’s a problem, that’s a no go,” Juliano said. “We deal with the business of running a household through phone calls and text messages, so when we have time together we’re focused on each other. You don’t have time for bickering.”

Hire tax help. If you’re married, there may be tax consequences to living in different areas, particularly if localities have different tax rates and requirements. “It makes tax returns more complex,” said Gretchen Stangier, a financial planner in Oregon in the US. If you’re filing taxes in more than one state or more than one country, work with a professional to make sure you’re not missing anything.

Make sure your retirement is on track. One of the issues with maintaining separate households is that it’s more expensive—another rent or mortgage payment, a second set of furniture and kitchen wares, and travel costs. “Typically what happens is they have to reduce how much they’re saving for retirement,” Stangier said. Run the numbers to see whether your retirement plan will take a hit.

Understand what it means legally. If you are married, you have the same legal rights as any other married couple, whether you’re living together or not. But if you’re not married, your legal status — and rights and protections — depend on jurisdiction, and many places don’t grant rights to people who don’t live together.

“In some cases jurisdictions give cohabitation equal legal status to marriage,” said an article on legal rights for LAT couples in the Journal of Social Welfare & Family Law. Couples who cohabitate may have the ability to register as domestic partners, which can grant a variety of financial advantages. Make sure you know what you’re giving up by living separately.

Do it later: Have an end in sight. For most people, this kind of arrangement isn’t sustainable long-term. “A bicoastal relationship is going to be really tough for a decade,” Gandhi said. If you’re totally content living miles apart from your significant other indefinitely, it might be time to question whether this is the relationship for you. Juliano and her husband are looking toward his retirement in five or six years as their end game.

 “We’ll definitely spend more time together at that point,” Juliano said. “But the discussion about primary residence is ongoing.”

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