Los Angeles schools avoided a strike that would have disrupted classes for nearly 400,000 students in Southern California after the Los Angeles Unified School District and SEIU Local 99 reached a last-minute agreement in principle with support staff, according to the union and the district.

SEIU Local 99 announced early Tuesday on social media that it had reached a tentative deal with “major gains,” including raises and more hours. The district, in turn, said the sides had reached an agreement in principle with SEIU Local 99 and that schools would be open Tuesday while the parties worked to finalize the terms of a tentative agreement.

SEIU Local 99 said the tentative deal also included protections against subcontracting. The union added that the agreement stopped IT layoffs and increased staffing, and it told members to report to work as usual Tuesday.

The dispute had raised the prospect of a walkout involving multiple unions representing workers across the Los Angeles Unified School District. The district had prepared for a strike that could begin Tuesday if a deal was not reached, with teachers, principals and other staff prepared to walk out.

Unions representing teachers and principals had already reached tentative contract agreements with the district over the weekend. In addition, the three unions representing about 70,000 workers had pledged to go on strike if any of the three failed to reach a tentative agreement.

The agreement with SEIU Local 99 also marked a contrast with an earlier standoff in 2023, when Local 99 workers went on strike and teachers joined them for three days. AP reported that in that earlier episode, about 150 of the district’s 1,000 schools remained open, in part because administrators stayed on duty to help keep schools operating.

In its announcement to members, SEIU Local 99 thanked other unions and the Los Angeles community, saying the “victory belongs to ALL of us,” while the district said the tentative agreement would keep schools open as details were finalized.