A customer gets stamps at a post office in San Jose, Calif., in December. (Paul Sakuma/Associated Press)

Postage rates jumped Sunday for the first time in 21 / 2 years as the U.S. Postal Service hopes to generate more revenue amid historic losses.

First-class postage stamps now cost 45 cents each, a price jump that officials anticipate will generate an additional $888 million in annual revenue. The rate increase, first announced in October, does not affect the use of Forever stamps purchased before Sunday.

In a separate development, negotiations between the U.S. Postal Service and two of its labor unions reached an impasse Friday that may eventually require a ruling by an arbitrator.

Postal and union officials announced late in the day that separate talks had collapsed between USPS and the National Association of Letter Carriers and the National Postal Mail Handlers Union. Contracts with both unions, which represent a combined 242,000 postal workers, expired in late November. Negotiations were extended twice before failing Friday.

Under the rules of postal labor negotiations, the parties may next engage in talks with a mediator if both sides agree. The mediation process generally lasts about two months, USPS said. If those talks fail, both sides would most likely turn to a third-party mediator, who would determine the final details of a new labor agreement. By law, arbitrators are not required to consider the Postal Service’s financial condition when making a final ruling.

Federal law prohibits postal workers from striking during a labor impasse.

NPMHU — which represents mostly back-room mail handlers — thanked its members Friday for their continued patience during the talks.

NALC President Fredric Rolando said Friday that his union’s negotiations had been “innovative, professional and productive,” adding that “a negotiated agreement is in the best interests of the parties, the businesses that rely on us and the nation we serve.”

NALC hired former Obama administration car czar Ron Bloom in October to advise the union on negotiations and to develop business proposals for USPS. Those proposals have not been released.

Clarification: An earlier version of this article incorrectly implied that Sunday’s stamp price increase was tied to an impasse in postal labor talks. The stamp price increase was announced in October. Negotiations with NALC and the NPMHU began in late November.

Additionally, an arbitrator in postal labor negotiations is instructed by law to consider all issues raised by the parties involved and is not required to consider any one condition — the Postal Service’s financial status or worker productivity, for example — more than others in making a final decision.

Follow Ed O’Keefe on Twitter: @edatpost

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