Heating bills may be eased for as many as 18,000 familes in Montgomery and Prince George's counties this winter as federal guidelines open up the fuel assistance program to more households.

Dec. 1 is the date set for local agencies to start taking applications that will bring qualified households from $127 to $400 for the winter, depending on the type of fuel used, family income and region of the state. The state has $28.2 million to distribute to fuel and utility companies to help pay the heating bills of eligible families.

The big difference this year is that instead of receiving a flat rate, eligible households can get an amount based on income and type of fuel, under a formula that gives more assistance to lower-income families but raises the maximum income allowed for eligibility.

In Montgomery and Prince George's counties, the cutoff last year for a family of four was an income of $9,313. This year it is $13,630. A family of three this year can have a total income of $11,940 and still receive assistance; a family of two an income of $8,940 and a household of one an income of $4,910.

The checks to cover part of a household's heating bill are sent to the fuel or utility company, not directly to the household. The funds come from the federal government's Department of Health and Human Services and are administered by Maryland's Community Programs Administration of the Department of Human Resources.

"This year we should be able to help a lot of people who fell between the cracks last year -- who were just a dollar over the maximum income," said Mary Bladen of Montgomery's Community Action Agency.

Last year applicants were required to present an unpaid fuel bill. This year they show proof of income and a copy of a fuel or utility bill that bears their account number.

Montgomery County residents may telephone 279-1014 for information or go to the energy assistance program office at 50 Monroe St., Room B03 in Rockville, Monday to Friday, 8:30 a.m. to 5 p.m. Prince George's County residents should call 699-2662 for information. Prince George's applications are accepted at the County Services Building, 5012 Rhode Island Ave., Hattsville, from Monday to Saturday, 8:30 a.m. to 5 p.m. starting Dec. 1. Applicants should telephone for the names and addresses of other offices in the county that will take applications.

Montgomery County expects to distribute benefits to between 5,525 and 6,840 households, and Prince George's to between 10,275 and 12,720.

Bladen said she is certain that Montgomery County has at least that many qualifying households. "Every time we go to a meeting they say, 'why, you all don't have any poor people.' But we have more than people really realize. aI don't know how that stigma will be taken off. We do have a lot of poor people," she said.

Last year 2,000 households in Montgomery and 2,800 in Prince George's County received the heating assistance.

Prince George's County, with 50 percent of its population living in apartments, will benefit by easier application procedures for renters. Last year renters needed a certificate from the landlord that every rent increase after July 1 was for energy reasons. Landlords were reluctant to divulge their rent-setting policies and few renters were able to qualify, according to Stephen Hannestad, deputy director of Prince George's County's Emergency Preparedness Office.

This year apartment dwellers who qualify by income level, whose rent is not subsidized and whose heating costs are included in the rent, can receive assistance if they have a signed agreement from the landlord specifying the type of fuel being used in the building and that the payment will be deducted from the rent. Checks are made payable to the landlord or jointly to the landlord and tenant, depending on the type of agreement the landlord has signed.