Mayrhofen is the terminus of the Zillertalbahn, the narrow-gauge railway from Jenbach. Jenbach has mainline rail connections toward Innsbruck, Salzburg, Vienna, and Munich, so arriving without a car is straightforward.
Driving is also easy in normal conditions, but a car is not needed once you are in town. The centre is walkable, and ski buses connect Mayrhofen with other lifts in the valley during the winter season.