If you're buying or refinancing a home, watch out for new fees that add $250 to the cost of every $100,000 you borrow.

Consumers with credit scores below 680, and who want to borrow 70% or more of the home's value, will pay even more.

The new charges are being imposed by Freddie Mac and Fannie Mae, the two government-chartered companies that buy or guarantee 40% of all home loans made by banks and mortgage companies.

While the fees will be paid by lenders when they seek to sell the loan, they'll almost certainly pass that cost on to borrowers through higher interest rates or closing costs. These new fees went into effect on March 1.

Every loan that conforms to Freddie Mac and Fannie Mae guidelines is a potential target for their 0.25% "post-settlement delivery fee."

That includes virtually all mortgages for less than $417,000 that aren't insured by the Federal Housing Administration and aren't considered subprime loans.

If you're not making a down payment of at least 30% and your don't have good credit, you'll pay an additional fee of:

• 0.75% if your credit score is between 660 and 679.
• 1.25% if your credit score is between 640 and 659.
• 1.75% if your credit score is between 620 and 639.
• 2% if your credit score is 619 or lower.

Many in the housing industry have criticized the new fees.

"It's certain to be more difficult for the housing market to regain its footing when steps are being taken to drive up mortgage costs," says Jerry Howard, executive vice president and CEO of the National Association of Home Builders. "This is the exact opposite of what needs to be done."

But Freddie Mac and Fannie Mae argue the fees reflect the greater risk they face with home values declining in many areas and more borrowers defaulting on their loans.

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