Donald Trump promised to give away his $400,000 presidential salary. And he kept that promise, publicly announcing each gift — at least, for his first 3½ years in office.

Then, in the middle of last year, the announcements stopped.

Trump’s White House never said where — or even if — he donated the last $220,000 of his salary, covering the final six months of 2020 and the first 20 days of 2021.

Now, six months after he left office, it’s not clear where Trump donated that remaining salary — or if he donated it at all.

Trump gave all his previous donations to federal agencies, paying out $100,000 every quarter. But The Washington Post surveyed all major federal agencies, and none has reported receiving anything from Trump after a gift in July 2020.

The Post also asked for confirmation of the gifts from Trump’s business and from the lawyer who helped arrange the donations. Neither responded. At Trump’s post-presidential office, a spokeswoman promised to seek answers — and then stopped responding to questions.

The dollar amount of these potential donations is small, in comparison to both the federal budget and to Trump’s personal holdings.

But the lack of information about them raises questions about a promise that was key to Trump’s self-image. He talked about these donations repeatedly as president — at the White House and on the campaign trail — often saying he did not get enough credit for the sacrifices he made.

“It’s a lot of money. Whether you’re rich or not, it’s a lot of money. And I did it, and nobody cared. Nobody — nobody said, ‘Thank you.’ Nobody said, ‘Thank you very much,’ ” Trump said at a White House briefing in March 2020.

Trump first promised to forgo his salary in 2015, during the first months of his campaign. But the Constitution requires the president to be paid, so Trump chose to take the money and then give it back to specific federal agencies. Trump often said he was the first president to give away his salary, but he was wrong: Herbert Hoover and John F. Kennedy both did it previously.

Trump’s first donation, in April 2017, was to the National Park Service, to help repair historic battlefields. It was announced from the White House press room by then-press secretary Sean Spicer, as the interior secretary and a Park Service official held up the check for cameras.

“It is every penny that the president received from the first quarter,” Spicer said then. “. . . It’s from January 20th, noon, forward.”

At least 13 other donations followed, all for $100,000, and spread among eight different Cabinet departments. This pattern appeared to contrast with Trump’s pre-presidential history with charitable giving: In 2016, The Post documented how, as a private citizen, Trump had made bold promises to donate to charity but did not follow through.

As Trump’s term went on, his gifts often highlighted his political priorities at the moment, indicating messages he was trying to send, or crises he was trying to solve.

He donated to a Transportation Department infrastructure program in early 2018, during one of his many doomed attempts at holding “Infrastructure Week.” (That one was derailed by the revelation that Trump’s attorney Michael Cohen had paid hush money to an adult-film star who claimed she had an affair with Trump.)

He donated to the Department of Veterans Affairs in 2018, while the agency was in turmoil: Trump had fired one director and withdrawn a nominee to succeed him. And, as the coronavirus pandemic threatened to consume Trump’s presidency in May 2020, Trump gave to the Department of Health and Human Services.

Then-press secretary Kayleigh McEnany said that gift would support research on covid-19 treatments and prevention measures, “so that we can safely reopen.”

Trump’s last known gift came on July 23, 2020, according to government documents. Trump gave to the Park Service again, “to support its efforts in repairing and restoring our national monuments,” according to a letter that Trump’s attorney Sheri Dillon sent the Park Service along with the check.

Trump had previously threatened to prosecute anyone who damaged monuments or federal property in the massive protests that followed George Floyd’s death at the hands of Minneapolis police.

After that gift: nothing. Or at least, nothing public. Neither Trump nor his White House announced any further donations.

Trump did continue to talk about his past charity. Throughout 2020, he often spoke about these gifts with a tinge of bitterness, lamenting that the news media did not talk more often about the donations.

“I’m the only president that did not accept a salary, which surprised me. It’s $450,000. The only reason I mention it is they never talk about it,” Trump said at a campaign rally in Arizona in October 2020, getting the history and the amount of his salary wrong.

He continued: “They never write about that. If I ever didn’t give it up, there would be headlines, ‘Trump refused.’ ”

In recent weeks, The Post contacted 15 major federal departments, including the eight that Trump had given to before, plus five agencies whose leaders attend Cabinet meetings. None provided any confirmation of a gift from Trump after July 2020.

That is not proof that the gifts were not made, however. Some of the major departments declined to comment. And The Post did not survey every single agency or office of the federal bureaucracy — a list so long that even the government itself has trouble keeping track. Official estimates of the number of federal agencies range from 118 up to more than 600, depending on how “agency” is defined, according to a 2018 report by the Administrative Conference of the United States.

The Post also contacted two different spokespeople for Trump’s post-presidential office. On June 10, spokesman Jason Miller wrote back, “Let me inquire and get back to you.” But he did not provide details, and later left Trump’s office.

Liz Harrington replaced Miller as Trump’s spokesperson. “I will try to track this down,” she wrote on July 21, when The Post asked again. Since then, Harrington has not responded to queries about the pledged donations.

As a former president, Trump is entitled to a government-funded pension of $221,000 per year. As of Thursday, he had been paid $102,482, according to the General Services Administration. In contrast to his presidential salary, Trump has made no promises to give the pension payments away.