King of the Hill originally ended its TV run on September 13, 2009 , when Fox aired the series-finale episode “To Sirloin with Love” as part of season 13.

A small wrinkle: four additional episodes from that same final production season first aired later in syndication in May 2010 , which is why some episode lists or streaming platforms appear to end the show in 2010 instead. However, those sources still treat “To Sirloin with Love” (aired September 13, 2009) as the intended story finale of the original run.

So if you’re asking “when did King of the Hill end?” in the sense of the big final network episode, the answer people usually give is: September 13, 2009. ✅

TL;DR: The show’s planned finale aired September 13, 2009 , even though a few leftover episodes trickled out in May 2010 via syndication.

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