Details of the agreement with the stagehands were not disclosed, but Matthew Loeb, president of the International Alliance of Theatrical Stage Employees, said the deal includes mandatory cost reductions from management and an independent monitor to track budget performance.
"We've always been willing to contribute to a solution that will keep the world's best operas in front of the world's greatest opera fans," Loeb said.
Fifteen unions representing about 2,500 chorus singers, orchestra musicians, stagehands, carpenters and others had been negotiating on and off since February. Their contracts expired July 31.
Musicians from the two largest Met unions reached tentative four-year deals Monday. The orchestra and chorus agreed to cuts of 3.5 percent and 3.5 percent more within six months.
The Met management also wanted to slash pensions and health care benefits, which remained intact.
The deals must still be ratified.
Most orchestra and chorus members at the Met made about $200,000 last year, including overtime costs they blame on Gelb's penchant for extravagant productions.
With the lockout deadline approaching the 11th hour several weeks ago, a federal mediator stepped in to try to bring the two sides closer. Gelb's lockout deadline was extended several times while a financial analyst conducted a study of company accounts.
The stagehands were the largest bargaining unit that had not reached a tentative agreement before Wednesday.
Negotiations will continue with eight smaller unions including those representing scenery painters and costume and makeup artists.