While there are a few financial practices that foster a happy, healthy life together, there are plenty to avoid as well.
Once you walk down the aisle, every money-minded decision you make - from saving for retirement to going out to lunch - affects your partner as well.
And while there are a few financial practices that foster a happy, healthy life together, there are plenty to avoid as well.
Business Insider spoke with multiple financial and relationship experts about how successful couples handle and talk about money. Here are eight things thriving couples never do:
They don't have different goals
Successful couples come up with goals together and check in frequently to make sure they're on the same page. Financial goals set the course for the rest of your life goals - Should we blow our money on a trip to Italy or save up to buy a home? - so it's important for couples to make sure they want the same things.
"While you may have different ways you handle your money on the day to day, when you know what you're both collectively working towards for the long term, you'll be able to make decisions that help you get closer to these goals," Pamela Capalad, CFP and founder of Brunch and Budget, told Business Insider.
One person never controls everything
As partners in marriage, it's natural to split up responsibilities. I'll cook dinner if you do the dishes. You clean the bathroom, I'll tackle the laundry. And in a lot of household areas, that works. But big financial decisions should always be handled together, even if one person is routinely responsible for quotidian tasks like buying groceries or paying bills.
If there's too much control by one person it can ruin a marriage, Pam Horack, CFP and "Your Financial Mom" at Pathfinder Planning LLC, told Business Insider.
"I've heard stories about 'my husband doesn't give me any money for anything' or 'I spent $5 on lunch and my husband yelled at me.' That's not really a money issue, that's a control issue, and so that's something that needs more help than just spending $5 or $10 on lunch," she explains.
They never avoid talking about money
Just as each relationship is unique, each couple's financial situation is as well. Spouses should be comfortable creating an open dialogue around money, where they can share any thoughts, plans, or ideas they have without fear of judgement.
"Couples do best when they have ongoing dialogues about their perpetual issues," Michael McNulty, a Ph.D. at The Chicago Relationship Center and master trainer with The Gottman Institute, told Business Insider. "If they fail to have ongoing dialogues about the ones that are most challenging to them, that can cause problems, and certainly money is one of the ones that can be most problematic. It's a basic need and it can really become an issue for people when they aren't on the same page."
If money becomes a point of contention for any reason, avoiding the issue will only prolong it.
"With something as important as money, if they don't have a comfortable ongoing dialogue, then what ends up happening is that matters don't end up getting talked about or discussed as they unfold," McNulty says.
They don't forget the details
Insurance. Estate planning. Naming a guardian for your children. The little things that might feel like another tick off your to-do list at the time add up to a lot in terms of future preparedness, and smart couples know not to put these things off.
Though often overlooked, estate planning documents, such as wills, are key factors in a successful financial future. As soon as they walk down the aisle, couples should think about naming beneficiaries, healthcare proxies, and powers of attorney. When kids come into play, it's important to name guardians for them as well, Katie Gampietro Burke, CFP at Wealth by Empowerment, told Business Insider.
It's also important to evaluate your insurance needs and double check that you're properly covered. The biggest financial mistake Sophia Bera, CFP and founder of Gen Y Planning, sees 30-somethings make is being underinsured - especially if they have another person depending on them, such as a spouse or children.
Bera recommends getting a term life insurance policy that's seven to 10 times your salary - enough to be able to cover your income, pay off a mortgage, and take care of your kids if anything were to happen to you.
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Successful couples never live above their means.
They never live above their means
Just because you can technically afford a $500,000 house doesn't mean it's the best choice for your family or your finances. Purchasing a home at the top of your budget ties up cash you could be putting toward other goals, such as travel, college funds, or retirement savings.
"Spend less than you think that you need to," Horack advises.
She emphasizes that "everything we have … it's all temporary." Will you downsize after your kids head off to college? How long will you have your car before trading up to a newer model? At the end of the day, many 'big' purchases aren't as permanent as they seem.
They don't hide their financial pasts
Understanding where your partner is coming from regarding their money philosophy is crucial to finding common ground and developing compromises that work for both of you. Was money tight when your spouse was growing up? Had they been deceived about money in a prior relationship? Has handling money been an issue for them in the past?
"If you get those stories back and forth, often it's easier for partners to understand one another," McNulty says.
It can be difficult to open up about money, but it's ultimately necessary.
"It's a sore subject, but you should still have that conversation," Burke says. "It's definitely not an easy one, [but] it's an important conversation."
They never cover up their mistakes
If you forget to pay a bill or spend too much on a silly purchase, it's tempting to cover it up and keep your partner from ever finding out. But don't. Successful couples come clean to each other about their money mistakes - no matter how small.
Hiding mistakes "can lead to distrust, and that's one of those root causes of people having some issues along the way," Horack says.
"Be honest about your mistakes because the other person can't help you if they don't know about them," she adds. Remember: You're a team.
They're never secretive
Successful couples "never hide [money] from each other and they never use it as a point of resentment or as a weapon in a conversation," Capalad says.
From revealing their credit card debt to discussing day-to-day purchases, couples in successful marriages aren't secretive about money. Rather, they're open and honest with each other about everything, down to even the tiniest details.
"They will find out one way or another," Capalad says. "There is a lot of embarrassment and shame when it comes to sharing your money situation. It can represent mistakes you've made in the past, decisions you regret, and take a big toll on your self worth. These are all feeling you should be able to share with your spouse and work through together."
As soon as they get married - or ideally, before - successful couples show their entire hand to their partner. That means coming clean about their salaries, credit card debt, student loans, credit score, and anything else that might affect their financial future as a couple.
"They should sit down and have a very open and honest discussion about their money and what they have," Horack says.