Area gas and electric utilities, reflecting rising costs, are imposing sharply higher requirements for deposits from late-paying customers and, in the case of one utility, from some new customers.

The largest increase has come from Virginia Electric and Power Co., which in September doubled the amount of many deposits. Potomac Electric Power Co. is up about 20 percent from year-ago levels.

Washington Gas Light, while continuing to collect about the same size deposit as before from District of Columbia customers, has raised requirements for Maryland and Virginia late-payers over the past year by 10 percent to 11 percent.

The deposits, designed to ensure payment of a final bill, are tied to consumers' energy use and so the increases are a direct result of the rise in gas and electricity prices, utility officials said.

Vepco now requires a $150 deposit from many late-paying customers and from some new residential customers who have either electric air conditioning or heating. It previously required $75 from such customers. For residential users who have neither electric air conditioning nor electric heating, the deposit has risen to $75 from $35.

The company will accept a smaller deposit from a customer whose electric bills for the two highest consecutive months of use in the past year are lower than the $75-$150 ceilings, said DennisHedgepeth, a Vepco spokesman. "We charge whatever is the lower amount -- their two months of electricity consumption or the $75-$150," he said.

The deposit also is required of a new Vepco customer without any previous satisfactory record of credit with an electric utility or when the customer's credit cannot be established, Hedgepeth said.

Unlike Vepco, neither Pepco nor WGL has such a requirement for new customers. In the case of late-paying customers, however, both say that anyone required to post a deposit generally must pay $100 or an amount equal to two months' worth of electricity, based on actual or estimated bills for a period of maximum usage at the customer's home. Under the D. C. Bill of Rights, instead of a deposit, the utilities will accept a one-year written guarantee of payment from a responsible third party

At present, the average deposit for Pepco residential customers, based on their electricity use, is $67, compared to $56 last year. That is a 20 percent increase. The average deposit now for WGL residential customers is $117 in Virginia, up 11 percent from last year's average of $105, and $78 in Maryland, up 10 percent from $71. The D.C. deposit for both years averages $73.

All three companies generally allow customers to pay deposits in three equal monthly installments. In addition, they typically review the customer's records on a regular annual basis and return the deposit when bill-paying habits show an improvement.

The interest paid on the deposits ranges from six percent to eight percent, depending on the regulatory commission requirements.

Five percent to six percent of customers at Pepco and WGL have been required to post deposits. Vepco did not have its percentage available.

In determining who is required to post a late-payment deposit, Vepco "does look at individual circumstances, but generally, if the customer receives cutoff notices twice in six months, he will be asked to post a security deposit," said Hedgepeth.

Pepco's rules depend on the jurisdiction. In the District of Columbia, for example, a customer may have to make a deposit if he has been delinquent in excess of 45 days at least three times within the previous 12 months.

In its handbook for Maryland consumers, WGL says a residential customer may be required to place a deposit for failure to pay a bill within a reasonable period after receiving a turn-off notice or if the gas is disconnected for nonpayment.

In Virginia, a consumer may be required to make a deposit if payments have been late three times within a 12-month period, if the gas is disconnected for nonpayment or if a bill is two or more months overdue.

In the District of Columbia, a customer may have to provide a deposit when the account has been overdue more than 45 days on three or more occasions in the past 12 months or if the gas is disconnected for nonpayment.