WASHINGTON » Average U.S. rates on fixed mortgages fell this week near record lows, providing more incentive for Americans to buy homes and refinance.

Mortgage buyer Freddie Mac said today that the average rate on the 30-year loan dipped to 3.32 percent. That’s below last week’s rate of 3.34 percent. And it’s just above the 3.31 percent, the lowest rate on records dating to 1971.

The average on the 15-year fixed mortgage declined to 2.66 percent from 2.67 percent last week. The record low is 2.63 percent.

The rate on the 30-year loan has remained below 4 percent all year, helping spark a modest housing recovery.

Sales of newly built and previously occupied homes are up from a year ago. Home prices have increased. And builders are more confident in the market and are responding by starting construction on more homes.

Rising prices encourage more people to sell their homes. And they lead to more buying, in part because some start to worry prices could eventually rise further.

Lower mortgage rates also have persuaded more people to refinance. That typically leads to lower monthly mortgage payments and more spending. Consumer spending drives nearly 70 percent of economic activity.

Still, the housing market has a long way to a full recovery. And many people are unable to take advantage of the low rates, either because they can’t qualify for stricter lending rules or they lack the money to meet larger down payment requirements.

To calculate average mortgage rates, Freddie Mac surveys lenders across the country on Monday through Wednesday of each week. The average doesn’t include extra fees, known as points, which most borrowers must pay to get the lowest rates. One point equals 1 percent of the loan amount.

The average fee for 30-year loans was 0.7 point, unchanged from last week. The fee for 15-year loans also was steady, at 0.6 point.

The average rate on a one-year adjustable-rate mortgage declined to 2.53 percent from 2.55 percent. The fee for one-year adjustable-rate loans ticked up to 0.5 point from 0.4 point.

The average rate on a five-year adjustable-rate mortgage rose to 2.70 percent from 2.69 percent last week. The fee was flat at 0.6 point.