Cheats for New Super Mario Bros. U for Wii U

Complete a level and jump on the flagpole with the timing to get:

Fire Flower : Last 2 digits equaling 33 or 34
Ice Flower : Last 2 digits equaling 55
Star : Last 2 digits equaling 88 or 99
Super Accorn : Last 2 digits equaling 77
Super Mushroom : Last 2 digits equaling 11, 22, or 66

There's an easy trick that works on every boss except Bowser, Bowser Jr., Kamek, and Giant Sumo Bro. When you're first in the room and after you first attack them, wait for them to come out of their shell then right when they do, if you're quick enough, attack them again before they even get the chance to strike back. Do the same thing one more time, and you'll have defeated a boss quickly.

If you earn all 5 stars on your profile you can visit Toad Houses repeatedly without them becoming inactive And previously inactive Toad Houses will become accessible again!

After you complete the game the first time, and you have unlocked Superstar Road, you can get the Propeller Hat and Penguin Suit power-ups (you know, the ones from New Super Mario Bros. Wii). They are made available from the Toad Houses located there. Once you get them, they can be used in any level in the game.