Rewards cards aren't always worth the trouble

Q: I'm being offered a new credit card by the bank that has my home mortgage account. It's a home-rebate credit card with 1 percent of purchases applied to the principal of my mortgage. Do you think it's worth having? How will a new card affect my credit score?

M.W., via e-mail

A: This offer from your lender leaves New York-based certified financial planner Erika Safran distinctly underwhelmed.

"I should spend $1,000 to reduce the principal on my mortgage by $10? So what?" she says. "I would have to spend $100,000 in one year to reduce it by $1,000."

So while it may sound like a nice feature, Ms. Safran places little value in it.

She is not averse to credit cards that offer bonuses, mind you. But she would just prefer one that was a little richer with its rewards.

A word of caution from her on picking up new credit cards: They'll increase the amount of credit available to you, potentially reducing your credit score.

Submit your question to Steve Dinnen at money@csmonitor.com