'I Do' Diligence: Five Financial Tips for Newlyweds

"You need to decide if you are going to have separate or joint accounts and how you are going to manage the checkbooks in these accounts," Armstrong says. "If you decide to have a joint account, make sure everyone knows what's going in and out to avoid overdraft problems."

One area couples should strongly consider combining, he says, is insurance. If both spouses have insurance through their employers, they should compare who has the better benefits and go with that one.

But one thing no couple likes to discuss before marriage is the grim reality of the 50% divorce rate in the U.S. Because half of all marriages fail, it's important to keep this in mind and have some assets set aside for yourself should you find yourself on your own again.