When it came time to plan San Francisco Pride this year, Suzanne Ford, the organization’s executive director, reached out to some longtime corporate sponsors to ask how they planned to support the event.

Their abrupt responses stunned her: Not at all.

Several of the event’s largest sponsors — including Comcast, Anheuser-Busch and the beverage company Diageo — told Ms. Ford that they would not be providing funding this year. The companies, which together provided over $200,000 to San Francisco Pride in 2024, each told her that supporting the event was no longer in its budget, she said.

“It was totally shocking,” Ms. Ford said, adding that some of the companies had supported San Francisco Pride for decades. “It was like somebody in your family just all of a sudden saying, ‘We don’t want to be involved with you anymore.’”

With only weeks left to lock in sponsors for the summertime events, Pride organizers across the United States say that many longtime corporate sponsors are suddenly being evasive about their financial commitments or abandoning their support entirely. While some companies cited tight budgets or economic uncertainty, Pride organizers see another factor: President Trump’s widening crusade against diversity, equity and inclusion, which has prompted corporate America to retreat from such initiatives.

“There’s a lot of fear of repercussions for aligning with our festival,” said Wes Shaver, the president of Milwaukee Pride. Many corporations he has spoken to are worried that the Trump administration will classify funding Pride events — one of the signature L.G.B.T.Q. festivals on the calendar — as a diversity, equity and inclusion effort, and that they’ll be punished or penalized. “Everyone’s afraid,” he said.

In recent weeks, Booz Allen Hamilton, Deloitte, Comcast and the auto dealership group Darcars have dropped their sponsorship of WorldPride, to be held in Washington, D.C., organizers said.

Andi Otto, the executive director of Twin Cities Pride, said that some longtime sponsors were leaving his calls and emails unanswered, and that his organization was about $200,000 behind its funding goal.

And Hampton Roads Pride in Norfolk, Va., has had some sponsors reduce their donations, while others have postponed decisions, said Jeff Ryder, the organization’s president.

This is a sharp reversal from past years — when corporations clamored to have their logos be seen at Pride events — and is creating deep unease among many L.G.B.T.Q. people.

“The tone has definitely changed,” Mr. Shaver said. While none of his sponsors have officially dropped out, Mr. Shaver estimates that he will lose about $50,000 in corporate funds this year, a 30 percent reduction from last year.

To adjust, he plans to scale back some performances, curb marketing plans and abandon hopes to hire big-name acts.

Pride Toronto is also taking a hit, organizers said. So far, it is short over $300,000 — out of a total budget of around $5.6 million — because corporations with U.S. ties have pulled out or reduced their donations, according to Kojo Modeste, the organization’s executive director. The event plans to cut one of its five stages, shorten performances and cancel its signature “Island Party” event on the Toronto Islands.

Nissan, one of the companies that pulled out of Pride Toronto, said in a statement that its decision not to sponsor the event this year was “due to a re-evaluation of all our marketing and media activations in a variety of activities.”

Corporate sponsorships help pay for security, insurance, permitting and equipment rentals. But for some groups, the cuts could reverberate beyond this summer’s Pride events. In Washington, the funding gap is endangering an endowment planned as part of WorldPride to support local L.G.B.T.Q. organizations that provide housing, food, clothing and group therapy.

A spokeswoman for Comcast declined to say why the company was withdrawing its sponsorship of WorldPride and San Francisco Pride, but said it was supporting smaller Pride events in California, including in Oakland, Silicon Valley and Sacramento. Diageo declined to comment. Anheuser-Busch, Booz Allen Hamilton, Deloitte and Darcars did not respond to multiple requests for comment.

John Paul Rollert, an adjunct associate professor at the University of Chicago Booth School of Business, said that many organizations worry “that they will be subject to heightened scrutiny and perhaps even reprisal by the current administration” if they support D.E.I.-related efforts.

While many companies blamed budgetary issues or potential economic headwinds, “I don’t believe that for one moment,” Mr. Rollert said. “Supporting a Pride event is not a particularly expensive undertaking. This is a fear of potential reputational harm that might come from the administration turning its spotlight on them.”

Ms. Ford had hoped to raise $2.3 million from corporate sponsors for San Francisco Pride this year, but as of mid-March had secured only $1 million. Insurance, security and medical services alone cost over $1.2 million, she said, prompting her to seek new corporate sponsors and solicit individual donations.

Many organizers said that most sponsors were sticking with them, and that some had even increased their donations. But the cooling support from some has refocused attention on how reliant large Pride events are on corporate backing.

For decades, companies grew increasingly comfortable associating their brands with L.G.B.T.Q. communities, said Matt Skallerud, the president of Pink Media, which specializes in L.G.B.T.Q. marketing. But that began to change in 2023, when a marketing campaign by Bud Light with the transgender influencer Dylan Mulvaney provoked outrage from the right and a boycott of the beer.

Months later, Target faced a backlash over its Pride Month store displays. After Target scaled back the displays, there came another backlash, this time from the left.

“At that point, a lot of other companies said, ‘Whoa, I think we need to slow down,’” Mr. Skallerud said. Some began to dial back spending on Pride-related marketing and events.

Since returning to the White House in January, Mr. Trump has ramped up his anti-D.E.I. efforts. After he issued an executive order instructing federal agencies to investigate “illegal D.E.I.” in the private sector, Mr. Skallerud said that many companies pulled the plug on such efforts. In recent weeks, Paramount, Google and Goldman Sachs have become the latest big-name companies to roll back D.E.I. programs.

The retreat — at a moment when many L.G.B.T.Q. people feel under threat — has added to criticism that corporations only support their community when it benefits them financially, a practice called “pinkwashing” or “rainbow capitalism.”

It suggests, Mr. Skallerud said, that companies “were only in it halfheartedly, and they weren’t completely our partners.”