Super Mario Galaxy
Mail Toad was one of the Toads who, along with Luigi, escaped Peach's Castle after its capture by Bowser. He later became a part of the newly made Toad Brigade, alongside Hint Toad, Bank Toad, Yellow Toad and its leader Captain Toad. Eventually, the Brigade made their way to Honeyhive Galaxy, where they met Mario and decided to help him in his quest to locate Power Stars, giving him one they found earlier. Afterwards, they set out to adventure through various Galaxies and find Power Stars, using the Starshroom, a starship built for them by Lumas at the Comet Observatory.
Mail Toad often delivered letters from Princess Peach and Luigi to Mario.
Due to the destruction of Bowser's Galaxy Reactor at the Center of the Universe, Mail Toad, along with the rest of the Brigade, was subsequently consumed by the black hole that destroyed the Universe. The Universe Reset caused by the Lumas to fix everything, recreating the Universe up to shortly before the beginning of the Star Festival. Mail Toad, with no memories of the previous adventure, found himself back in the Mushroom Kingdom.
Super Mario Galaxy 2
Since the events of Super Mario Galaxy were effectively erased from history, Mail Toad would once again join the Toad Brigade created by Captain Toad, although this time they would depart from the Mushroom Kingdom, in a Starshroom built by a Luma from Lubba's crew. He later met Mario in Spin-Dig Galaxy and joined him in travelling alongside the Starship Mario. Together, the Toad Brigade assisted in finding numerous Power Stars.
Super Mario Odyssey
After Bowser once again kidnapped Princess Peach, The Toad Brigade set out to adventure around the world, looking for Power Moons. Mail Toad helps run a Crazy Cap store from their Starshroom.