In fact it came out as more important than good looks, wealth, the car they drive or whether they own their own home.
What's more, once you've found The One, managing your money is the way to keep them. A huge 89% said 'good financial planning' is important for happy relationships, while 2 in 5 admitted financial issues had been partly responsible for a relationship breakdown.
Speaking about the survey, relationship expert Jo Barnett, said, "I've seen many couples falling out of love over their financial differences. When you're in a relationship it's no longer just about you, so the more open and honest you can be upfront about spending, saving and earning, the more respect and harmony you have later down the line."
Here, the Money Advice Service offers its money advice for couples...
Relationship advice for handling money worries as a couple
1. DO set aside time to talk about money
Weekly, fortnightly, monthly . . . it's up to you. It's important that both of you have a general idea of the family's finances. Are there any big expenses coming up? How much is in your bank account?
2. DON'T avoid talking about money until it's too late
If you think it's going to end in an argument, it's tempting to bite your tongue. But leave it too long and the molehill may turn into a mountain. Find time to talk about money issues when you're both relaxed, and don't spring a big money talk on your partner by surprise.
3. DON'T talk about money issues when you're angry
You won't solve any of your money issues by fighting or shouting. If the bank statement doesn't make pleasant reading, take a deep breath until you can raise your concerns calmly and rationally.
4. DO remember that two people rarely see eye to eye on money
Just because you might argue over money (most couples do), it doesn't mean that your relationship is heading for the rocks. Some people are spenders and some are savers, you just need to work to find some middle ground.
5. DON'T talk about money all the time
Even if you're determined to take control of your finances, it's not good to go on about it all the time. Put your family life first and only talk about money during the times you've set aside.
6. DO view money as a means to an end
Managing your money isn't about spending as little as possible, never being overdrawn, or building up a nest egg that you're not allowed to touch. It's about spending your hard-earned cash on the things you need and enjoy, and setting and respecting financial goals for the things you both feel strongly about.
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