NEW YORK (MainStreet) — No doubt about it, the biggest factor in marriage falling apart is money.

"Arguments about money is by far the top predictor of divorce," says Sonya Britt, assistant professor of family studies and human services and program director of personal financial planning at Kansas State University. "It's not children, sex, in-laws or anything else. It's money — for both men and women." 

Britt recommends that newly married couples, or couples thinking of getting hitched, talk to a financial planner as soon as possible.

She also advocates pulling each spouse's credit reports so the partners can "talk through how to handle finances fairly for both individuals." (To find a dependable financial adviser, visit The Association for Financial Counseling, Planning and Education website.)

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The best move is to plan as early as possible for money and marriage issues, well before wedding bells ring. Unfortunately, according to Ann Margaret Carrozza, a lawyer and finance expert specializing in estate planning, very few couples want to have that talk. A recent study suggests 68% of recently engaged couples have negative feelings toward the duty.

Having a "money talk" is crucial, she says.

"You know their favorite color, their weird habits and other random facts. But do you know about your partner's finances?" she says. 

Here's Carrozza's list of seven "musts" for each spouse to learn about the other's financial situation:

1. Their credit score. "It can affect the house you get, the loans you receive, insurance policies, and even a possible job," she says.

2. How much they owe. "It can takes years to pay off, which could lead to you having to take a particular job or even cutting back on big price necessities like a car or even appliances," she adds.

3. How much they make. "An income figure will give you an idea of how much you need to contribute to joint expenses, as well as know the standard of living you'll be entering," Carranza says.

4. How much they save. "Is your spouse or future spouse saving for their retirement," she asks. "How are you two going to save for future expenses or even college educations if you decide to have kids?"

5. How much (and why) they spend. "You'll need to know what your partner considers a necessity and how much they rely on their credit card," she advises.

6. How they feel about estate planning. "Nobody wants to think about it when they are young, but things happen and it's better to not worry and to be ready," Carranza says.

7. Their financial past and future. "Your partner's parents' money habits and the money environment they grew up in shape the way your partner looks at money," she says. Additionally, know any financial obligations coming out of a previous divorce, especially any cash changing hands on a regular basis. "If your partner has children from a prior relationship, it is critically important to know how much financial support he or she plans on giving them."

"Also, If your partner plans to pay for his daughter's third wedding, you may want to know about that in advance," she adds.

Don't let money issues torpedo a good relationship. Know going in where each of you stand, and work out a financial arrangement that breeds good will and cooperation. If you can manage that, you're halfway to a long, healthy relationship, where money arguments are rare.

— By Brian O'Connell for MainStreet