UPS and the Teamsters union representing some 340,000 UPS employees nationwide are rapidly approaching the end of their national contract, which expires at midnight July 31.

There’s been much back-and-forth this summer as the deadline approaches, though a recent stalemate appears to be lifted, with the sides set to return to the bargaining table Tuesday. Experts warn that a strike could disrupt the supply chain and result in delivery delays for some customers.

As contract talks get down to the wire and the threat of a nationwide strike draws near, take a look back at the negotiation process between the shipping and logistics giant and the union.

A looming UPS strike: How we got here

August 2022: UPS Teamsters (the union representing UPS rank-and-file workers) issue a call-to-action campaign one year ahead of the July 31, 2023, contract expiration. The campaign launch coincides with the 25th anniversary of the 1997 UPS Teamsters strike. That 15-day strike by some 185,000 workers was the most recent time the UPS Teamsters went on a nationwide strike.

March: Regional unions begin the bargaining process with UPS over supplemental contracts for their employees. Teamsters wanted the 40 supplement contracts to be tentatively agreed to before national negotiations began. Most were completed before national negotiations.

April 17: National negotiations between UPS and the Teamsters begin.

June 13: The sides reached a tentative deal on air conditioning, including air conditioning systems, new heat shields and fans for the company’s vehicle fleet. 

June 16: With 97% of union members voting, Teamsters pass a strike authorization vote, allowing the union to strike if deemed necessary.

June 19: UPS and the Teamsters reach consensus on 55 non-economic issues and turn attention to economic aspects.

June 22: UPS presents counterproposal to the Teamsters’ initial economic contract. Teamsters call it an “appalling” response.

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Late June: Tentative agreements are reached on all supplemental contracts, including for the final two UPS locations: Louisville and Northern California.

June 28: Teamsters Local 89 members in Louisville hold a practice picket, part of a national call for UPS Teamsters to hit the practice picket lines. Local union leadership says a strike would be a 24/7 operation at Worldport, with its approximate 10,000 union members rotating picket line shifts.

Teamsters Local 89 UPS members in Louisville voted 99% in favor of authorizing strike action, indicating their willingness to strike.

June 28: UPS Teamsters walk from the national bargaining table and demand UPS present its last, best and final offer by June 30. The International Brotherhood of Teamsters declares a nationwide strike “is imminent."

June 30: UPS gives the Teamsters a revised counterproposal the union said had “significant movement on wages and other economic language,” persuading the Teamsters to return to the bargaining table. UPS pledges to reach a new contract by July 5.

July 1: Teamsters General President Sean M. O’Brien says the July 5 deadline is important to hit to give the union time to ratify the contract ahead of the July 31 expiration. The union leader says Teamsters won’t work past July without a fully ratified contract.

The union announces it reached a tentative agreement with UPS on stopping forced overtime on drivers' days off, making Martin Luther King Jr. Day a paid holiday and ending a two-tier wage system the union said was unfair to drivers who are not classified as full time.

July 5: Teamsters and UPS end contract talks around 4 a.m., unable to reach agreement on a new five-year contract. Both sides say the other walked from the negotiations. No date is given to resume talks.

Mid July: UPS starts “continuity training” for non-union employees ahead of a possible strike. These non-union workers are likely to see additional workload expectations should a strike occur.

July 17: White House press secretary Karine Jean-Pierre says the White House is "confident both sides are going to come to an agreement" and doesn’t plan to intervene.

July 18: Teamsters General Secretary-Treasurer Fred Zuckerman leads rallies at Louisville Centennial Hub and UPS Worldport ‒ the largest sorting and logistics facility in the U.S. ‒ as part of a nationwide rally tour. He says the contract is 90% complete and that remaining hold-ups are over part-time workers.

July 19: Twelve days ahead of their contract expiration with UPS, Teamsters say negotiations would resume the following week.

July 21: Contract negotiations are set to resume July 25, the Teamsters announce.

July 31: At midnight, the contract between UPS and Teamsters will expire. If an agreement isn’t reached, Teamsters are set to strike, triggering what would be the largest single-employer strike in U.S. history. Teamsters leadership has said as long as a full tentative agreement is reached by midnight July 31, union members would work during the approximate three-week ratification period.

Contact business reporter Olivia Evans at [email protected] or on Twitter at @oliviamevans_. Growth & development reporter Matthew Glowicki can be reached at [email protected], 502-582-4000 or on Twitter @mattglo.