The majority of these will be Christmas episodes, but a few might happen on other holidays, or at any random time of year. (The list may also include standalone TV specials.) There may be some "Gift of the Magi" parody episodes I haven't included here, if I'm unaware of them.
Episodes on this page are listed in chronological order of original airdate.

Aired in 1955, in the only season of The Honeymooners (at least, the only season in which that was a regular series, as opposed to sketches on other series). I never saw it, but there is at least half of a "Magi" plot between Ralph and Alice.

This special first aired in 1978, during (but not part of) the tenth season of Sesame Street. One part of it included a "Magi" plot between Bert and Ernie.

Aired in 1987, in season four of Kate & Allie. Not a holiday episode (though it aired just a couple weeks after Christmas, the gifts are for the anniversary of their families moving in together). While I don't remember the details, this episode is what most often comes to mind when I think of "Gift of the Magi" plots.

Aired in 1988, in season fourteen of Saturday Night Live. I don't think I ever saw this sketch until 2017, when I watched it online while making this page. The "Magi" plot is between Donald and Ivana Trump (played by Phil Hartman and Jan Hooks).

Aired in 1999, in season two of Futurama. A small part of the plot involved a "Magi" story between Zoidberg, Amy, and Hermes.

Aired in 2016, in season six of My Little Pony: Friendship Is Magic. Not a holiday episode (unless you count "Pie Sisters' Surprise Swap Day"). But it does nearly become a "Magi" plot between Pinkie and Maud.