Despite record cold temperatures this winter and record costs for heat, Washington residents and businesses are paying their utility bills almost as fast and as frequently as in the past.

According to spokesmen for Washington Gas Light Company and Potomac Electric Power Company, the city's two largest utilities that provide heat, delinquency rates rose during The Winter That Was by between 8 and 14 per cent.

Both companies said the effect on their cash flow, their service, their scheduled repairs and their readiness for next winter has been minimal.

There are two reasons, spokesmen said:

Both companies offered specially extended time payment plans to customers who fell into arrears on their bills. And both companies made extensive efforts to contact deliquents personally so terms could be arranged.

In addition, both companies suspended long-standing policies of cutting off service automatically once a bill went unpaid for two months.

Pepco began a no-turnoff policy on Dec. 17 and suspended it March 23. Washington Gas began it Jan. 31 and has not rescinded it, although the company plans to "soon," a spokeswoman said.

Both companies said that no significant number of area residents has taken advantage of the no-turnoff policy.

Pepco spokesman John Grasser said that, of 458,900 Pepco customers in the metropolitan area, 8 per cent were in arrears at the end of February. At the same time in 1976, the deliquency figure was 5 per cent. At the same time in 1975, the figure was 6 per cent, Grasser said.

The 8 per cent delinquency figure is by far the lowest among Washington area utilities. Grasser said that was because only 6.3 per cent of the area's homes are heated by electricity, and because Pepco offered a nine-month payment plan to delinquents. All other area utilities, and most oil companies, offered plans of no more than six months.

Grasser said that recent rate increases may have contributed as much as the harsh winter to the icrease in delinquency.

Pepco won a 13 per cent increase in the District last December. It won a 9 per cent increase in Maryland in February, 1976, and an increase of another 8 per cent in Maryland this past January.

Pepco serves the District, the Maryland suburbs and a handful of customers in Northern Virginia.

A Washington Gas spokeswoman said her company's delinquency rate at the end of February was "about 14 per cent" above last year's.

In February, 1976, Washington Gas delinquents totaled approximately 35,000. This February, the spokeswoman said, the total was 39,681 - 18,867 in the District, 13,328 in Maryland and 7,486 in Northern Virginia.

The District's ratio of delinquents to total customers is far higher than ratios in the other two jurisdictions, the spokeswoman said. About 40 per cent of the company's customers are in the Maryland suburbs, and 30 per cent each in the District and Northern Virginia.

The spokeswoman said that only about 2,000 of the nearly 40,000 delinqents have taken advantage of specially extended time payment plans. The total unpaid debt of the delinquents represents "approximately $5 million," the spokeswoman said.

Virginia Electric Power Company is the area utility hit hardest by delinquency in the wake of the winter. A spokesman for the company, which serves all of Northern Virginia, said delinquency is up "over 30 per cent over last year," despite a no-turnoff policy and efforts to arrange time payment plans for delinquents.

"I really can't put a reason on it," the Vepro spokesman said.