MOST people who took out jumbo mortgages during the financial crisis got hit with high interest rates as lenders and investors recoiled from anything that seemed even remotely risky. Now that market conditions have improved, some of these borrowers are looking to refinance into lower-rate mortgages, but they may not want to start over with a 30-year loan.

One possible solution might be to refinance into a 20-year loan. Right now, rates on these mortgages are low enough that someone in the third year of a 30-year loan can shave years off the payment term without increasing the monthly payment much, if at all.

"The benefit to the borrower is saving thousands of dollars in interest, because of the shorter term," said Thomas Pinkowish, a mortgage industry consultant in Essex, Conn. "The drawback is the higher payment."

But sometimes the increase is small, said Stephen Habetz, the president of the Threshold Mortgage Group in Westport, Conn.

For instance, a borrower who took out a $1 million loan four years ago at the prevailing rate of 5.875 percent, Mr. Habetz said, would have a monthly payment of $5,915. The remaining balance today would be $945,000. That same borrower could now, with a good financial profile, qualify for a 20-year mortgage at 4.75 percent with no points, he said.

Assuming refinance charges of $5,000 were added into the new loan, the new payment would be $6,139, or $224 more than the old loan. But, Mr. Habetz added, "with a 15-year loan, at the current rates, the payment is $7,251, which is a lot more painful."

By switching to a 20-year loan, the borrower would pay off the mortgage six years sooner than the current schedule, saving nearly $380,000 in interest payments. Even if the borrower sold the home in five years, he or she would still have built $66,000 more in equity with the new loan than the old one, Mr. Habetz said.

He said that since interest rates on 20-year loans dropped to current levels about a month ago, the mortgages have grown in popularity among borrowers of jumbo mortgages -- loans of more than $729,750 in areas with the highest-cost housing.

Demand has been especially strong, he said, among borrowers with loans of more than $1 million, because that is the threshold beyond which borrowers cannot deduct mortgage interest from their federal income taxes.

Mr. Pinkowish noted that 20-year loans mainly appeal to people financially comfortable with the payment, and those who want a mortgage-free retirement and plan on staying in their homes.

To find the loans, borrowers can contact brokers like Mr. Habetz or use an online service like Lendingtree.com, which last week offered 20-year mortgages in Manhattan fromSterling National Bank and Block Financial Resources. A borrower with a 20 percent down payment and a 720 FICO score would qualify for a loan (of less than $417,000) with a 4.75 percent rate at Sterling National.

Meanwhile, Hudson City Savings Bank, which serves parts of the tristate area, offered a 20-year mortgage for 4.75 percent last week. Thomas Laird, the bank's chief lending officer, said that three years ago these loans accounted for about 1 percent of mortgage business. This year, that figure has reached 6 percent.

Hudson City does not lend in Manhattan, Brooklyn or Queens, because of the high concentration of multifamily housing and co-ops. Borrowers should be prepared to make down payments of at least 20 percent, and their housing debt should generally not exceed 34 percent of their gross income, Mr. Laird said. Total debt, he added, should not exceed 42 percent of income.

Hudson City does not review a borrower's credit score. Rather, Mr. Laird said, the bank looks at the borrower's "overall track record, their income, their assets."

"Anybody taking a 20-year loan typically has stronger income, and more ability to service the debt," he said, "so they're not first-time home buyers struggling to get in."

By Bob Tedeschi