Washington-area consumers can buy some food items and other goods for less today than a year ago despite the steady upward push of inflation.

The bargains include such basics as bacon and eggs, blue jeans and long-distance telephone calls.

Most of the products whose prices have fallen in the last year are grocery store foods, which have benefited from good weather and more plentiful crops.

In all, federal statisticians who track consumer prices found 15 price reductions among the 240 items that are included when the Consumer Price Index is computed.

Consumer prices rose 1.4 percent during January, according to the latest index, published last Frdiay. Over a year, that would amount to an annual inflation rate of 18.2 percent. Until now, inflation has been running at about 13 percent.

The index prices are averages for the entire country; individual prices locally will vary from store to store and product to product.

Pork prices, for example, are down 9 percent compared to a year ago.The pork category includes bacon, down 12.1 percent; pork chops, down 10.1 percent; ham other than canned, down 10.1 percent; canned ham, down 6 percent and other pork products, down 7 percent.

At Safeway's 130 supermarkets in the Washington metropolitan area, one pound of the house brand bacon now sells for $1.19. The same bacon cost $1.39 a year ago.

Eggs declined more modestly 1.2 percent.

In January of 1979 prices for oranges, tomatoes and lettuce were up because of bad weather. Now, however, oranges are selling for 5.7 percent less than at that time and tomatoes are down nine-tenths of 1 percent.

The biggest price drop, however, was for lettuce, which plummeted 42.2 percent between January 1979 and January 1980.

An improved supply of produce and pork wasn't the only market force that eased the pain of paying for consumers. A price war among jean specialty shops helped, too.

The official price index shows that men's and boys' jeans and trousers dipped four-tenths of 1 percent during the year. But that is an average. Some stores didn't lower prices at all. Others went down by a significant amount.

At The General Store's eight outlets in the Washington area, a pair of hard Levi western-style denims now sells for $13.98. That's $1 below the price in effect early last year.

At one point during the past year, jean prices at The General Store were even lower. They dropped to $9.98 just before Christmas at the height of the price war. Chain President Syd Lewis said the war with The Gap and Pants Corral chains started in an effort win a larger share of the market.

Lewis said the store sells low to attract consumers who will buy additional regularly-priced merchandise once they are inside the store.

The Consumer Price Index also registered a decline in the price for most women's and girl's clothes and sportswear. That apparel slipped by 1 percent, officials said.

But an attempt to find an example of this trend locally was unsuccessful.

"We have not noticed any items going down in price this year, compared to last year," said a representative for Woodward & Lothrop.

Government index figures are based on a wide-ranging survey of store prices, so that an increase in prices at some stores combined with decreases at others can result in an overall reduction. Another factor which can affect government averages, an official at the Bureau of Labor Statistics said, is the special sale price offered on merchandise. He said more widespread special sales during January 1980, compared to the year before could have lowered the average.

The lower telephone toll prices reflect a reduced federal tax. Effective Jan. 1, the excise tax dropped 1 percent in the latest of a number of annual reductions that ultimately will eliminate the tax.Last year, telephone users paid a 3 percent federal excise tax on telephone bills. This year, the tax will be 2 percent.

A daytime toll call from the District of Columbia to New York City now costs $3.46 for 10 minutes if the caller dialed directly. The price last year was $3.50.

Calls within a state are down in some instances. A telephone call between Rockville and Annapolis that costs $2.28 now would have cost $2.30 a year ago.

But in Virginia, local rate increases have wiped out the impact of the federal tax reduction on intrastate telephone charges. The base fee for a four-minute daytime conversation between Alexandria and Norfolk now costs three-cents more than it did last year.

For consumers who want to compute the effect of all this on their own family budgets there is one final price reduction to consider. It is the electronic calculator. Prices are down generally.

A basic model calculator made by Texas Instruments and priced at $20 today would have cost $30 last year.