ABC said 6.26 million viewers watched Kimmel as he used sincerity and humour to thank his supporters while addressing remarks he made on September 15 about the man accused of assassinating conservative activist Charlie Kirk.
It was the highest-rated regularly scheduled episode of the late-night show, which typically attracts an average of 1.42 million nightly viewers, ABC said.
Jimmy Kimmel Live! achieved the ratings milestone, even though the show did not reach about one-quarter of American households.
ABC affiliates in several major markets did not carry the show, which aired hours after network parent Walt Disney lifted Kimmel's suspension.
On social media, Kimmel's monologue attracted nearly 26 million views, ABC reported. That included 15.3 million views on YouTube, and another 6.3 million on Instagram.
Network parent Disney's decision to cut short Kimmel's exile marked a high-profile act of corporate defiance in the face of Trump's escalating crackdown on perceived enemies in the media through litigation and regulatory threats.
Disney was also under pressure from Kimmel's fans, some of whom were cancelling subscriptions to the company's streaming services Disney+ and Hulu. Kimmel alluded to that in his monologue, joking the company had asked him to read some remarks on the air.
"To reactivate your Disney+ and Hulu account, open the Disney+ app on your smart TV or TV-connected device," he read. Kimmel defended political satire against "bullying" from Trump and officials in his administration.
Kimmel's voice choked with emotion, moments after he took the stage to a standing ovation, and he said: "It was never my intention to make light of the murder of a young man. I don't think there's anything funny about it."
Last week, Kimmel said Trump's supporters were eager to characterise Kirk's assassin "as anything other than one of them" and accused them of trying to "score political points" from Kirk's killing.
Before Tuesday's broadcast, Trump said on his Truth Social online platform that he "can't believe" ABC gave Kimmel back his show, and hinted at further action against the network.
Trump's post called Kimmel "yet another arm" of the Democratic National Committee, and characterised the comedian's jokes about the Republican administration as "a major illegal Campaign Contribution. I think we're going to test ABC out on this."Â
Previously, Trump had said Kimmel was fired for "bad ratings."
The late-night format has been struggling for years, as more viewers have abandoned cable television and migrated to streaming. Younger viewers, in particular, are more apt to find amusement on YouTube or TikTok, leaving smaller audiences and declining ad revenues for traditional TV.
Nexstar Media Group and Sinclair both opted on Tuesday to keep "Jimmy Kimmel Live" off their combined 70 owned and operated ABC stations, which account for about 23 per cent of US households. That meant the show was not seen over the air in places like Seattle; Salt Lake City, Utah; Nashville and New Orleans, among other markets. It also did not air in Washington, D.C.
Nexstar said it is continuing to evaluate the status of the show, which it will continue to pre-empt on its ABC-affiliated local television stations.
