How refinancing affects your credit scores

This post comes from Gerri Detweiler at partner site Credit.com.

It hardly seemed possible that mortgage rates could get much lower, but they have. Freddie Mac reports that 30-year fixed-rate mortgages reached an all-time record low of 3.4% this week, down from last week's 3.49%.

Homeowners are taking notice and refinancing their mortgages. But if you're on the fence because you are afraid that refinancing (again) will hurt your credit, relax.

"It will neither help nor hurt your score in the short term," says Anthony Sprauve, director of public relations for myFICO.com. "Any impact will be minimal and brief. The true impact will be how you manage the new mortgage over time."

While that makes refinancing sound like a no-brainer, there are a couple of potential traps you'll want to watch out for.

The first is the impact of shopping for a new loan on your credit scores. Each time you apply for credit, that produces an "inquiry" into your credit history. "The typical additional inquiry can be expected to lower a credit score by five points or less," says Barry Paperno, a credit-scoring industry veteran and manager of the Credit.com forums.

But in the case of mortgage loan inquiries, "you can incur any number over a focused period of time, such as 14 or 45 days, and they will only count as one inquiry," Paperno explains. "Also, while on your credit report for two years, inquiries are counted for only the first year by the credit-scoring models."

Steve Ely, CEO of eCredable.com, agrees, adding: "Like most things in the science of credit scoring, the thicker your credit file, the smaller the impact on your credit score."

The take-away? If you are going to shop for a new lower-rate home loan, it's a good idea to do so in a relatively short period of time.

The other risk when you refinance? A missed mortgage payment. While this trap isn't common, if you're affected you can see a significant drop in your scores.

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It works like this: You are approved for a new loan to pay off the current loan. Your loan officer tells you that you can skip this month's payment on your current loan because the new loan will take care of it. That's true -- provided the loan closes and funds on time. But if the payment from the new lender arrives more than 30 days after your current payment to your old lender was due, that lender may consider that last payment late. And one late payment can really hurt your scores.

So keep an eye on the calendar and if it looks like you might be cutting it close, talk with your lender and loan officer about making that mortgage payment to keep your good credit intact.

If all goes smoothly, though, your credit report should list the old loan as paid in full with a zero balance. Pay the new loan on time and your credit will be just fine. Not to mention your budget.

More on Credit.com and MSN Money:

• How a mortgage can help (or hurt) your credit
• Can you really get your credit score for free?
• How can I get a mortgage after credit problems?
• Calculator: Should I refinance?
• Student loans haunt home shoppers
• Estimate your credit score for free