Current Mortgage Rates -- Dec. 28: Rates Creep Up for Most Loans

Here's what's going on with mortgage rates at the end of December.

Mortgage rates drifted slightly upward on Monday Dec. 28 for all but the 15-year fixed-rate loan. Here's what you need to know about current mortgage rates as December draws to a close.

Data source: The Ascent's national mortgage interest rate tracking.

30-year mortgage rates

The average 30-year mortgage rate today is 2.782%, up .002% from an average of 2.780% on Christmas Eve. For each $100,000 borrowed at today's average rate, your monthly principal and interest payment would add up to $410. Total interest costs would add up to $47,578 per $100,000 borrowed over the life of the loan.

20-year mortgage rates

The average 20-year mortgage rate today is 2.615%, up 0.001% from an average of 2.614% on Christmas Eve. You'd be looking at a principal and interest payment of $535 per $100,000 borrowed at today's average rate. During your entire loan repayment period, you'd pay total interest costs of $28,514 per $100,000 borrowed.

Interest costs are lower over time, but monthly payments are higher as compared with the 30-year fixed-rate loan. When you pay off your debt a decade sooner, your total costs fall but your monthly payments rise since you have less time to repay your loan -- and thus pay interest for less time.

15-year mortgage rates

The average 15-year mortgage rate today is 2.205%, down 0.021% from an average of 2.226% on Christmas Eve. A mortgage loan at today's average interest rate would cost you $653 per $100,000 borrowed. The total costs of interest would add up to $17,538 per $100,000 borrowed at today's average rate.

Since you cut even more time off your repayment period with a 15-year fixed-rate mortgage, your monthly payment is even higher but total interest costs are lower. You'll need to decide if you'd rather be debt-free much faster even if that means paying higher monthly payments.

5/1 ARMs

The average 5/1 ARM rate is 3.315%, up 0.123% from an average of 3.192% on Christmas Eve. Adjustable-rate mortgages are riskier than fixed-rate mortgages because your rate could go up -- which would mean your payment could go up too. When your rate begins adjusting in five years, there's a very good chance it will go higher since rates are currently near record lows. There's no benefit to taking this risk since you can currently secure a 30-year fixed-rate loan at a more competitive starting rate than the 5/1 ARM is offering.

Should I lock my mortgage rate now?

A mortgage rate lock guarantees you a certain interest rate for a specified period of time -- usually 30 days, but you may be able to secure your rate for up to 60 days. You'll generally pay a fee to lock in your mortgage rate, but that way, you're protected in case rates climb between now and when you actually close on your mortgage.

If you plan to close on your home within the next 30 days, then it pays to lock in your mortgage rate based on today's rates -- especially since they're so competitive. But if your closing is more than 30 days away, you may want to choose a floating rate lock instead for what will usually be a higher fee, but one that could save you money in the long run. A floating rate lock lets you secure a lower rate on your mortgage if rates fall prior to your closing, and while today's rates are still quite low, we don't know if rates will go up or down over the next few months. As such, it pays to:

• LOCK if closing in 7 days
• LOCK if closing in 15 days
• LOCK if closing in 30 days
• FLOAT if closing in 45 days
• FLOAT if closing in 60 days

To find out what rates are available to you so you can decide whether or not to lock in, compare rates from some of the best mortgage lenders. It's a good idea to get at least three quotes as rates can vary considerably from one lender to the next and even small differences in rate can add up over time.