Chevy Chase Federal Savings Bank, Maryland's largest savings and loan, will lay off more than 100 employees today, or 4 percent of its work force, in an effort to reduce operating expenses, Chairman B.F. Saul III said yesterday.

The layoffs are the first in the thrift's 21-year history and the latest in a series of work force reductions taking place at area financial institutions, most of which are suffering from the declining commercial real estate market and increased scrutiny from regulators.

Last week, Washington Bancorporation, parent firm of the National Bank of Washington, laid off more than 150 employees, or 15 percent of its work force.

And last month, Perpetual Savings Bank, the largest thrift in the area, eliminated about 200 unfilled positions from its payroll.

Saul said cutbacks at Chevy Chase were made largely in response to the competition, which is becoming leaner after years of uninterrupted growth and expansion.

"We want to maintain our independence; we do not want to sell out," he said. "This is something we felt we needed to do to maintain our plan of being competitive and independent. ... It's painful to do."

Other area banks and S&Ls that are cutting employees or are not hiring new workers include MNC Financial Inc., parent of Maryland National Bank; Equitable Bank; American Security Bank; United Savings Bank of Tysons Corner; and Ameribanc Investors Group, parent of Ameribanc thrift of Annandale.

According to the most recent statistics available from the D.C. Department of Employment Services, overall employment by banks and thrifts in the Washington area was down slightly to 40,000 employees in May from 40,200 in April.

And banking executives interviewed yesterday said they believe that trend will continue.

Saul said the action taken today will affect all levels of Chevy Chase personnel and will eliminate some small departments that were not very profitable, such as the thrift's boutique consumer lending operation.

Chevy Chase has long been recognized as a leader in customer service, with a total work force of 2,700 people, hundreds of whom were deployed to its branches to help customers.

However, that level of service also was accompanied by high expenses.

MNC Financial, also in an effort to cut costs, has eliminated about 1,000 positions over the past six months, resulting in about 400 employees being laid off.

Daniel Finney, spokesman for the company, said the reductions were completed June 30 and were caused by the company's merger with Equitable Bancorporation.

MNC is still in a "no growth" phase, Finney said, but it does not expect to make any more cutbacks.

United Savings Bank, which operates 15 branches in Northern Virginia, also has been downsizing since January and has fired about 140 employees, a 39 percent reduction in the thrift's work force.

John Lewis, head of personnel at the thrift, said most of those layoffs affected United Savings's branches and its mortgage subsidiary.

He said the bank is shrinking to help cut costs and meet capital requirements, the cash cushion bank owners must provide to protect the deposit insurance fund from losses.

For similar reasons, Ameribanc cut about 30 employees, or 5 percent of its work force, from its payroll last fall.

Spokesman David Campbell said Ameribanc is not hiring any new employees.