Riggs National Corp. has won a multimillion-dollar contract from the U.S. Treasury to act as clearinghouse for $286 billion the government collects electronically each year from citizens and corporations, the government and Riggs confirmed yesterday.

Riggs won the bid over nine rivals that include New York banking giants Citicorp, Chemical New York Corp. and Chase Manhattan Bank, sources close to the deal said. The $286 billion represents 200,000 "Fed wire deposit system" transactions that are sent to the government each year by computer and telephone wire rather than by check, money order or other paper document, according to Treasury officials.

The electronic payments represent about one-third of the nearly $1 trillion in payments the Treasury collects each year on behalf of 200 federal agencies. Payments include everything from taxes on income to leases on grazing land owed by the Department of the Interior, officials said.

Winning the contract is a coup for Riggs, which like most banks is looking to boost revenue from service fees as much as from interest charged on loans. For the Treasury, the contract is another step in the government's attempt in recent years to turn over as many operations as possible to private industry.

"We see the government as a natural customer for us," said Riggs spokesman David Palombi. "We're looking for fee income like anyone else, but we got in line for this one because we see the federal government as a natural market to expand in."

Riggs' contract runs for four years and can be renewed for four more. Riggs will earn as much as $5 million in fees during each four-year period, according to sources close to the contract, which was awarded in September but is to be announced next week.

Treasury officials stressed that no money will be transferred to Riggs, only information on when money is received, which agency is to get it and who sent it. The actual cash from transfers will remain in a Treasury account at the Federal Reserve Bank of New York, where the Treasury's electronic deposits are collected.

The new system, which will begin Dec. 1, is expected to earn the government $102 million in additional interest income, because the new system is expected to speed up the Treasury's receipt of money. "Hey, anyone would be proud of that," said Andrew Montgomery, a spokesman for the Treasury division that awarded the bid to Riggs.

Treasury officials said individuals or corporations send money to the government by wire rather than by check when they want a payment to arrive quickly, usually to meet a deadline or because they want quick access to a federally owned mine, oil well or other property.

As a clearinghouse, Riggs' major subsidiary -- Riggs National Bank of Washington -- will keep track of daily deposits that are made at the Federal Reserve Bank of New York.

Riggs will be linked by computer to the New York Fed and to the Treasury. The New York Fed will update Riggs continuously on deposits received. Using desk-top computers plugged into Riggs' computers, officials at the Treasury and at various federal agencies will be able to see what money the government receives within seconds after it is recorded in New York, Treasury officials said.

At the end of each day Riggs will send the government a paper copy of each day's transactions.

When Riggs becomes the Treasury's clearinghouse for electronic receipts, it will mark the first time the Treasury has turned to private industry to run such an operation.

Riggs and government officials said the confidentially of payments will be protected through a complex web of computer safeguards. To ensure that those safeguards work, a Treasury official will oversee the system and decide who can use it.

For sensitive payments, such as those to the IRS, extra precautions will be taken, Riggs officials said.

Riggs officials said the company was able to outbid competitors because it can use existing computing systems to create the clearinghouse