Increasing numbers of homeowners have mortgage rates above 6% and that is easing the so-called “lock-in effect” that has contributed to a national housing shortage, according to the online brokerage Redfin.

Nationally, roughly 17% of homeowners had a mortgage rate north of that figure at the end of last year, which is up 5 percentage points from the fall, the company said.

If trends continue, the share of homeowners with 6% or higher mortgage rates will double in the next three years, Redfin said.

As mortgage rates remain elevated, the so-called “lock-in” effect that has contributed to a national housing shortage is “easing,” Redfin said.  

This scenario refers to the huge cohort of homeowners who hold low-interest mortgages. Reluctant to give up sub-4% mortgages, they haven’t been willing to list their homes and move to a bigger home or downsize.

But Redfin said that’s been changing.

“For most people, it’s not realistic to stay put forever,” the company said. “Many Americans are growing accustomed to the idea that rates are unlikely to fall to pandemic lows anytime soon.”

Americans also have enough equity to justify a move and take on a higher rate, especially if they are downsizing or moving to a more affordable area.

“And finally, a rising share of Americans are mortgage-free, which means they’re not locked into any rate at all,” Redfin said.