It might reveal unexpected benefits.

"Economically, being a couple opens each individual up to the options available to both members of the party," Kristen Euriteg, certified financial planner and founder of Brooklyn Plans LLC, told us. "For example, if you have a couple with one freelancer and one salaried employee, the freelancer can get the health benefits of the employed person for less than on the open market."

Euriteg said she recently worked with a man who supported his partner while she went back to school to get her master's degree. The woman qualified for student loans, which she took out to refinance the man's credit card debt at lower rates and more flexible repayment terms, so they both reaped the rewards of being open about their money.

[Photo via Reshot]

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