Levels are a side-goal in Tomodachi Life. Miis will level up whenever their Happiness meter fills up, as a result of giving them Food, Items, Clothing, and solving their Problems.
When a Mii levels up, the player is able to give them gifts:
- Songs: A Mii will be able to sing that song at the Concert Hall
- Interior: 6 Interiors that are only available via leveling up. They will not appear in the Interior Shop.
- Gift: A gift that can be used by Miis in their apartment. Max is 8.
- Phrase: Miis can have their own personal phrases.
- Pocket Money: The player gives money from their own pocket to the Miis. The money is used to go to outer space, and a Mii will need $10,000 to achieve it.
When a Mii hits level 20, they get two additional options:
- Clothing: The player can give any item of clothing that's been bought for free.
- Hats: The player can give any hat that's been bought for free.
After hitting level 20, Miis will show the player their gratitude by giving them the Treasures Silver Coin or Gold Coin. Silver Coins are worth $100 each, while Gold Coins are worth $200 each.
The level cap is 99. However, they will continue to 'level up', but the number will not change.