Today's Mortgages -- Sept. 28: Mixed Results for 30-Year vs. Other Mortgage Types

With rates remaining near record lows, it's still a good time to lock in a rate if you're buying or refinancing a home.

Today's mortgage rates show very slight variation from recent days and recent weeks, with the 30-year loan ticking slightly downward and others up a bit. However, rates for all loans still remain near record lows. Thirty-year fixed-rate loans once again have average rates below 3.00% while 15-year fixed-rate loans have an average rate that remains below 2.50% for another day.

For those looking to buy or refinance a home, these rates remain extremely competitive and borrowers may wish to consider locking in their loan while rates remain near record lows. Here's what you need to know about today's rates.

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

30-year mortgage rates

The average 30-year mortgage rate today is 2.941%, down .007% from Friday's average rate of 2.948%. If you qualify for a loan at today's average rate, you will pay $418 per month in principal and interest for each $100,000 borrowed and total interest costs will come in at $50,634 per $100,000 in debt.

Check out The Ascent's mortgage calculator to see what your monthly payment might be and how much your loan will ultimately cost. Also learn how much money you'd save by snagging a lower interest rate, making a larger down payment, or choosing a shorter loan term.

20-year mortgage rates

The average 20-year mortgage rate today is 2.829%, up .02% from Friday's average of 2.809%. This is below the interest rate on a 30-year fixed-rate loan. But while the interest rate is very low, the monthly payment is higher.

On a 20-year fixed-rate loan at today's average rate, you would pay $546 in principal and interest per $100,000 borrowed and total interest costs over the life of the loan would add up to $31,058 per $100,000 in debt.

Total interest costs are much lower than with a 30-year loan because there's a decade less time when you'll owe interest. The catch, however, is that to pay off your home loan in just 20-years time, you'll have to make those higher monthly payments.

15-year mortgage rates

The average 15-year mortgage rate today is 2.441%, up .025% points from Friday's average of 2.416%. This rate is well below what you'd pay on a 30-year fixed-rate loan. But, as with a 20-year loan, monthly costs are higher while total costs are lower. The effect is even more pronounced here, as you're taking off another five years of repayment time.

Because you're paying off your loan so quickly, the monthly payment for a 15-year loan would total $664 in principal and interest per $100,000 borrowed and total interest costs over the life of the loan would equal $19,523 per $100,000 in mortgage debt.

5/1 ARMs

The average 5/1 ARM rate is 3.634%, up .162% from Friday's rate of 3.472%. A 5/1 ARM is an adjustable-rate mortgage with a starting interest rate that is fixed for the first five years. Unlike a fixed-rate mortgage, you do not know up front what total interest costs or monthly payments will be, as the rate could adjust after the initial five-year period.

There are times when taking out an adjustable-rate mortgage makes sense. Normally, this type of loan has a lower starting rate than a 30-year fixed-rate loan, so borrowers will take advantage of that low rate to get more affordable payments with a plan to refinance or sell before it could begin to adjust.

With the initial starting rate on a 5/1 ARM well above the rate on a 30-year loan right now, there is no advantage compared to a 30-year loan and thus no reason to take on the risk of rates going up after the initial five-year period.

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

Before you lock in your loan, you'll want to make sure you're getting the most competitive rate and terms possible. Not all lenders offer the same low rates, so you should comparison shop among the best mortgage lenders and secure quotes from at least three before you decide which loan is right for you.