Fallout 2 features same-sex marriage through opportunities to marry Miria or Davin, a sister and brother working at the slaughterhouse in Modoc, in a shotgun wedding regardless of the Chosen One's gender or party limit. This marriage is permanent unless Miria/Davin dies in some way, is sold to slavery, or is divorced at New Reno's Drunk Cupid Chapel in exchange for a bottle of alcohol. According to game designer Chris Avellone in 2019, nobody at Black Isle Studios working on the game was against the inclusion of same-sex marriage, and noted that "fans didn't seem to care" about it when playing the game. He believed the reason for this reception was because of it only being offered in Modoc, a tight-knit small town "where things can get wild and weird" that was more receptive to it than a more "modern" location like Vault City.

A hidden alternative ending can be achieved if the player were to allow thirteen in-game years to accumulate. Due to an overflow bug, Black Isle Studio's developers hard-coded the eery splash screen as a convenient workaround, with ambience accompanying the words "THE END" above broken city ruins and a flashing light in the distance.

A pair of Survival Recipes, "The Big One" Pancake and Carrion Kabobs, can be found in the back of the game's manual. While series co-creator Tim Cain kept a trend of including recipes in games he worked on, such as the manual for Fallout, it's unknown if he contributed these two recipes, as he quit Interplay Entertainment in the early months of the game's development.