From Detective Conan Wiki

Christmas, as an annual holiday, is also celebrated in Japan - without the religious connotations and an emphasis more on the Christmas Eve than the Christmas Day itself, though. Central to it are giving and receiving cards, presents and the typical Christmas cake to others to spread a feeling of happiness. The Japanese Christmas and its customs appear in the works of Gosho Aoyama a couple of times as a central plot element.

Plot overview

The Santa Claus of Summer plot overview

The whole plot, manga and anime alike, doesn't happen on that day, but, as the title says, revolves around recreating Christmas in the Summer in the hopes of getting Keisuke Hara to remember the number code he entered to activate the killer satellite.

Magic Kaito plot overview

Love on the Ski Slope on Christmas Eve (MKS: 6)

Star War (MK Manga: 14, MK1412: 12)

Yaiba plot overview

Immortal Kaguya (Yaiba Manga: 162)

This chapter was released on December 9th, 1992 and featured a Christmas-themed cover.

Detective Conan plot overview

Lex Vocalist Murder Case (Manga: 45-48, Anime: 42)

Department Store Stabbing Case (Manga: 939-941, Anime: 843-844)

Murder inside Café Poirot Case (Manga: 981-983, Anime: 885-886)

Heiji Hattori and Kazuha Toyama want to visit the Christmas lights in the 4th block of Ginza, but don't managa to do so because of a murder happening at Café Poirot Heiji gets involved in. Ran Mouri accompanies Kazuha to Ginza instead to see it.

Detective Conan non-canon plot overview

The Christmas Murder Case (Special Manga: 74-75)

Christmas Eve Gift (Special Manga: 96)

The Hidden Corpse (Special Manga: 154)

Black & White Christmas (Special Manga: 380-381)

Wishes of Christmas Eve (Special Manga: 435-436)