UPS and the Teamsters union, which represents some 340,000 workers at the package carrier, said Tuesday they reached a preliminary labor agreement that includes raises for full-time and part-time workers and narrowly avoids a potential strike that could have started as early as next week.

It was the latest in a series of labor agreements in which workers from pilots to aerospace manufacturing employees have lobbied for higher wages.

The deal is worth $30 billion, according to Teamsters general president Sean O’Brien.

“The union entered this fight committed to winning for our members. We demanded the best contract in UPS history, and we got it,” he said in a statement.

Existing part-time workers will get a raise of at least $21 an hour, if the workers approve the new contract, the union said. Part-time pay was a sticking point in the negotiations. Full-time workers will average $49 per hour. Current workers will receive $2.75 more per hour this year and $7.50 more per hour over the five-year contract.

The deal would also end mandatory overtime on drivers’ days off, according to a contract summary provided by the Teamsters.

“Together we reach a win-win-win agreement on the issues that are important to Teamsters leadership, our employees, and to UPS and our customers,” said Carol Tomé, CEO of UPS. “This agreement continues to reward full-time and part-time UPS employees with industry-leading wages and benefits, while retaining the flexibility we need to remain competitive, serve our customers, and keep our business strong.”

The workers have yet to ratify the tentative agreement. UPS employees represented by the Teamsters voted to authorize a strike after July 31 if the two sides did not reach an agreement. The work stoppage could have hit industries like retail that rely heavily on the package delivery giant.

The National Retail Federation applauded the tentative deal.

“UPS is an important partner of the retail industry and we are grateful to have reached an agreement with the Teamsters without disrupting the market,” said Matthew Shay, chief executive of the trade group, in a statement. “Retailers rely on stability within their supply chains, and this agreement will bring long-term stability, as well as security, to the millions of businesses and employees who rely on seamless and efficient last-mile delivery.”

Some recent labor negotiations have not produced new contracts, despite preliminary agreements. On Monday, rival UPS pilots fedex rejected a tentative labor deal, with 57% voting against the deal.

-CNBC melissa repko contributed to this report.