Firefighters who have been working without a contract for more than three years will see their pay jump 17.5% in coming months in a deal announced yesterday. Mayor Bloomberg and the head of the union that represents about 8,900 city firefighters appeared together at City Hall to tout the pact, which would make the raises retroactive to 2002.

“There has never been any question that these brave men and women deserve a raise,” Mr. Bloomberg said.

The Uniformed Firefighters Association president, Steve Cassidy, called the contract “a step in the right direction,” and added that he didn’t think the city could ever pay firefighters what they are actually worth. The contract, which still needs ratification by union members, calls for gradual raises of between 3% and 5% over four years. Firefighters would see most of the hike all at once because so much of the time covered by the deal has already passed.

Firefighters who have been with the department for that entire period would get their back pay in a lump sum that would average more than $15,000, city and union officials said. The new contract would expire in July 2006.

The deal includes some concessions by the union. Pay for new recruits would drop to $25,100 from about $36,000, although new hires would see their pay climb to $32,700 once they finish basic training.

The maximum base pay for a firefighter would rise to $63,309.

The union and city also reached an agreement on staffing levels that would prevent the city from cutting the size of many of its engine companies for five years. The deal is the latest in a string of collective bargaining agreements signed with city unions in the months leading up to Mr. Bloomberg’s re-election bid.

The city announced earlier this month that it would give its teachers a 15% raise over four years. Sanitation workers cut a deal for a 17.5 percent pay hike. A state arbitration panel in June awarded the city’s police officers a retroactive pay raise of about 10.25%.