The three major insurers of Equity Programs Investment Corp. mortgages have agreed to put up $43.3 million to offset defaults on the loans, clearing the way for a bailout of the troubled real estate tax-shelter firm, a creditors' committee announced yesterday.

David O. Maxwell, head of the Federal National Mortgage Association and chairman of the creditors' group, called the agreement "a milestone in our efforts" to resolve the situation.

EPIC is owned by Community Savings & Loan Association of Bethesda, and its troubles have crippled the institution, forcing the state of Maryland to place the thrift into conservatorship and freeze its deposits. More than 350 investment partnerships set up by EPIC went bankrupt in September after defaulting on more than $1 billion worth of mortgages and mortgage-backed securities.

The state last month accepted the bailout plan, which still must be approved by various regulators and the bankruptcy court.

Under the agreement, Ticor Mortgage Insurance Co., Mortgage Guaranty Insurance Corp. and Republic Mortgage Insurance Co. will place the money in an escrow account today. The money will be used to cover payments due on the mortgages for August, September and October.

Maxwell said the plan is structured to protect the savings and loan associations among the creditors from having to treat the loans as doubtful -- or "classified" -- assets for regulatory purposes. Many of these thrifts are in financial difficulty and classifying the EPIC loans would be a severe blow to them.

The plan would work this way:

After the loans are brought current, their terms would be changed. Creditors would receive payments at a rate of 9 percent a year -- most of the notes were originally 13 percent or higher -- though interest would accrue at 12 percent. The accrued but unpaid interest would be paid when the property is sold if the price is high enough.

The regular payments would come from rental income from the houses. To the extent that this income is inadequate, the insurance companies would make up the difference. The insurers would be required to bring the payments up to 9 percent in the first two years of the agreement, and to 7 percent thereafter.

Maxwell said that the workout is expected to take five years, and the 20,000 houses would be sold off "in an orderly way" during that time. The best properties would be sold first, he said, and any money left over after paying these mortgages would be used to keep up payments on the remaining loans.