From the Super Mario Wiki
Mario's House, also known as Mario's Pad and Pipe House, is the home of Mario and Luigi. The house first appeared in the German Club Nintendo series of Mario comics and was later featured prominently in the various Mario RPG games.
Additionally, Mario and Luigi's parents' house (and by extension, Mario and Luigi's first house), is shown at the end of Super Mario World 2: Yoshi's Island and the very beginning of Yoshi's Island DS. It resembles a Mushroom, like a Toad House.
 Club Nintendo
 Süße Weihnachten
Mario's House is shown several times in the Club Nintendo comic series. It makes its first appearance in "Süße Weihnachten." As the comic is set around Christmas, the house is decorated in a Christmasy style, and also has a Christmas tree. It resembles Mario's Pad from Super Mario RPG, as it is a very small house with apparently only one room. At the time of the comic's setting, Mario is not at home, but the door is opened. Bowser takes this chance to steal some sweets.
 Super Mario: Im Rausch der Geschwindigkeit
In Super Mario: Im Rausch der Geschwindigkeit, not much of Mario's house is seen, but it appears to be much larger than in its previous comic appearance. It also has a bathroom (just like in the later comic Super Mario: Die Verwandlung). The fact that it is multistory may imply that Mario lives in an apartment during the events of this comic.
 Super Mario: Coole Klänge
Super Mario: Coole Klänge shows for the first time that Mario and Luigi live in the same house. The comic also shows a radio, a saxophone and several guitars in their home.
 Super Mario: Verloren in der Zeit
The story Super Mario: Verloren in der Zeit even reveals the location of Mario's House, Pilzgasse 13, which translates to Mushroom Alley 13. Another possible translation would be Mushroom Way - the area near Mario's Pad in Super Mario RPG, though this similarity is probably coincidental. The house in the comic is very big compared to its counterpart in the games, and is covered with ivy. Not much is known about the inside, except that Mario has a TV.
 Warios Weihnachtsmärchen
Finally, the house is shown again in Warios Weihnachtsmärchen. In this comic, it is painted white and has a red door which reads MARIO in large letters. Nothing is known about it otherwise, except that it is decorated similar to the house in Süße Weihnachten.
 Super Mario RPG: Legend of the Seven Stars
During the events of Super Mario RPG: Legend of the Seven Stars, it is named Mario's Pad and is connected to Vista Hill to the west and Mushroom Way to the east. The actual house itself is named the Pipe House and sits in a small forested area. The interior of the house has a bed, a Fungi Light, a cuckoo clock, and a change of clothes hanging on the wall. Outside, several large wrenches are hanging up on the side of the house. Additionally, the house has a huge pipe sticking out of the roof. In fact, Mario falls through this pipe after Exor crashes into Bowser's Castle. Toad, who was waiting for Mario and Princess Toadstool outside, rushes into the Pipe House. However, instead of helping Mario, Toad quips "Lots of people use something called a 'door' to go in and out of their houses." Dry Bones hid his flag under the bed in this house.
 Paper Mario series
Mario's home was renamed Mario's House in the Paper Mario series (as well as Mario & Luigi: Superstar Saga). It is almost just a bigger version of the one in Super Mario RPG. The version in Paper Mario has a secret basement that Luigi had secretly added to the house, as he thought Mario would not find his diary there. Mario is able to check his battle statistics (as well as other statistics) and his mail here, he is even able to rest in his bed in Paper Mario. Mario can commonly come and visit his house, and is able to see Luigi doing something different every time, whether it be standing outside, or writing in his diary. In Paper Mario: The Thousand-Year Door, the house doesn't change much, but has a red and green theme, such as the red and green coffee mugs and toothbrushes. In Super Paper Mario, Mario has pictures of his Partners from the previous two games, but the house is other wise unchanged. In Super Paper Mario, the theme of his house is called "Mario Bros.' House".
 Paper Mario Area Tattle
 Dr. Mario 64
 Mario & Luigi: Superstar Saga
In Mario & Luigi: Superstar Saga, Mario and Luigi's house is seen in the opening where the worried Toad arrives to tell the Mario Bros. that Princess Peach's voice had been stolen. This version has a big portrait of Princess Peach, a small kitchen area, plumbing tools scattered around, and a bathroom. The brothers' room is located upstairs, with a red and green bed.
Outside, the house is pale yellow in color, have a red roof, a Star antenna and a chimney resembling a pipe. Princess Peach's Castle is also able to be seen from the home.
The music here is a remix of Super Mario RPG: Legend of Seven Stars.
 Dance Dance Revolution: Mario Mix
In Dance Dance Revolution: Mario Mix, Mario and Luigi's house has, depending on which was selected, a huge Mario or Luigi hat for a roof. It has also a green mustache-like decoration with a star in the center and is very small. There also was a river just down the path that flooded.
 Paper Mario series
 Mario & Luigi: Superstar Saga
 Name in Other Languages