Does Coco have a post-credit scene?

Coco has no post-credits scene in the ordinary sense. There is no extra story beat, no joke, no Dante gag and nothing setting up another film. If you are waiting for a stinger, there isn't one.

There is, however, something after the credits, and it is arguably the most affecting thing Pixar has ever put there.

Once the names have rolled, a card appears reading roughly: 'Día de Muertos is a Mexican heritage tradition with roots in indigenous culture. To learn more, visit your local library.' Then the screen fills with an ofrenda — a photo mosaic assembled from real photographs of the dead relatives of the people who made the movie. Crew members submitted pictures of their own grandparents, parents and great-grandparents, and the film ends by putting them on the altar.

The reason this lands so hard is that the entire film has just spent ninety minutes establishing the rule that governs its world: the dead persist only as long as someone living remembers them and puts their photograph on the ofrenda. Forget them and they fade. So the closing mosaic is not a dedication in the usual credits-crawl sense. It is the film's own mechanic, applied by the filmmakers to their own families, in public — the movie doing the thing it just told you to do.

So: no scene, and yes, stay.