Unmarried couples face special financial situations

Solot stresses that these documents are for couples that survive the initial getting-to-know-you phase and are in it for the long haul. A good place to start is with the cohabitation agreement, sort of a prenup without the nup.

"It doesn't have to be limited to issues regarding what if you break up. It can also be about how you'll handle your finances while you're together," she says. "What are the rules if you have a joint account? What's it to be used for? If you have a joint credit card, how much can you buy on it? A lot of couples find it helpful to have something they can refer back to that explains what the expectations are."

Rhode cautions new partners to get to know each other's credit history and spending habits before establishing joint accounts. After all, your continued good credit could depend on it.

"This is a trip-up even for married couples because if you have a joint credit card and you divorce, you divorce your spouse, not your credit report," he says. "So now you're left jointly obligated for the debt of somebody you can't stand."

The biggest money decision involves how you will pay the bills. Will you pool all expenses and share them according to ratios based on your incomes? Will you divide them? I pay these, you pay those or split the bills evenly?

Whatever method you choose, it's a good idea to make sure all your bills are getting paid in a timely manner.

Disclose your money style
"One law of nature is that savers attract spenders," says Rhode. "The mistake I see lots of people making is not looking over the bills together. It's you pay the cable bill and I pay the trash bill and everything remains separate so nobody has a clear picture of what's really going on. That's not helpful."

Stacy Whitman, who co-authored Shacking Up: A Smart Girl's Guide to Living in Sin Without Getting Burned with her attorney sister Wynne, suggests a couple schedule a money date and talk about financial goals and sources of irritation before moving in together.

"You could have different savings habits, different financial goals, different views about money in general," she says

Solot says financial frankness is especially important when an unmarried couple makes the leap to purchase a house.

You can take title as joint tenants, in which you are both equal owners and automatically receive the other's share if he or she dies, or as tenants in common, in which case you can own the house in unequal percentages and do not have automatic right of survivorship.

"It is common for people to bring different amounts of money and savings and income to the relationship," she says. "There often is some kind of imbalance there that you have to work around and find something that feels fair.

"It's really important to have explicit conversations about how you're going to do it."

Unmarried with children
Things get even trickier when you're unmarried with children.

According to attorney Wynne Whitman, if only one partner is the biological parent or legal guardian, the other partner has no financial obligation to the child. If the couple has a child together, however, courts will generally hold both legally responsible for the child as long as both parents' names appear on the birth certificate.

Unmarried couples should take steps beforehand to plan for the child's upbringing.

"If you're thinking about having a child together, it's a good idea to draft a co-parenting agreement and consult a family-law attorney in your area because state laws do differ," says Whitman. "This is particularly important for homosexual couples where one is the biological parent."

Her sister, Stacy, agrees: "You should see a family-law attorney to get some guarantees regarding child custody and child support in the event the two of you were to break up."

Bottom line: Cohabitation may appear more carefree than marriage, but it's also fraught with considerable financial risk. Draft the necessary agreements. They can help protect your credit and provide an effective blueprint to keep money issues from ruining your romance.

Jay MacDonald is a contributing editor based in Mississippi.