Marie Callender’s is offering a free slice of pie on Wednesday, March 14 in honor of Pi Day. You must bring in a coupon on the Marie Callender’s website, and buy one full-price adult entree in order to receive the free slice of pie.

The offer isn’t valid with the restaurant chain’s Kids Eat Free, Crave and Save Menu, Happy Hour Menu, Daily Dish Specials, Lunch Combos or Pair & Share Menu.

Guests can choose from over 20 different varieties of freshly baked pies, including the limited-time Celebration Cake Pie.