Washington ? Home buyers again need their own money to close a deal.

Lenders faced with growing piles of bad loans, even to borrowers once considered good credit risks, have clamped down on the no-money-down mortgage. The abrupt shift threatens to dash the hopes of millions of potential buyers, especially those shopping for their first homes.

Four out of 10 first-time buyers used no-down-payment mortgages in 2005 and 2006, according to surveys by the National Association of Realtors. But some lenders are now scrapping such loans completely. Others are pickier about who gets them. All figure that the more cash borrowers put down, the less likely they are to default.

“No-down-payment loans are just about near impossible to get right now,” said Jennifer Bridges, a real estate agent in Woodbridge, Va., at ERA Blue Diamond Realty. “We’ll have someone all lined up and then without warning, the lender will say: ‘It’s gone.’ It’s terribly depressing.”

National City Home Equity, a division of National City Bank, one of the nation’s big home lenders, stopped funding some types of zero-down loans this month, said Ken Carter, the division’s executive vice president.

“When home prices were appreciating and interest rates were declining, that product made sense,” Carter said. “Today, we’re on the opposite side of that coin, and it’s not prudent to be stretching.”

Washington Mutual, another big lender, in March stopped offering such loans to subprime borrowers, typically people with poor credit. It also reduced the size of loans to other borrowers.

Many years ago, a 20 percent down payment for a home was the norm. But as prices escalated, fewer people could afford that. After all, 20 percent of $500,000 – the cost of a middle-class suburban house in the Washington, D.C., area – is $100,000.