This fast-casual chain based in Athens, Ga., with more than 50 units, will sell pizzas for $3.14 and hold a giveaway for customers who download the Your Pie Loyalty app or use #yourpieday on social media. Customers who enter will have the opportunity to win free pizza for a year or a GoPro Karma drone with a Hero6 camera.

Based in Dallas, Pizza Inn, with over 150 units domestically and over 60 units internationally, will treat customers to a special Pi Day deal: any large, single-topping pizza and a medium “pizzert,” or dessert pizza, for $15.99.

This Milwaukee bakery will celebrate Pi Day with six different types of pie — apple, peach-blueberry, lemon meringue, cinnamon, Kentucky Derby and s’mores — available at $3.14 per slice.

Based in Washington, D.C., with over 25 units, &pizza will host free weddings for couples at local shops on Pi Day in partnership with Lyft, Milk Bar, UrbanStems and Framebridge.

Trader Todd’s in Chicago will feature a homemade Key lime pie with a coconut-rum graham cracker crust on its menu on March 14. Pies will be half-price at $4.50 all day in honor of the mathematical holiday.

For Pi Day fans, Hungry Howie’s, headquartered in Madison Heights, Mich., with over 550 units, will serve up a one-topping medium pizza at $3.14 each with the purchase of any regular Howie Bread from March 13-14.

The Rancho Santa Margarita, Calif.-based operator, with over 140 units, will ring in Pi Day with a pizza special: buy one pie and get the second one for $3.14. Those who join Pieology's digital membership program and present their welcome email upon purchase can redeem the discount.

The fast-casual pizza chain, headquartered in Pasadena, Calif., with over 245 units across 38 states and Canada, will commemorate Pi Day on March 14 by offering any build-your-own pie for $3.14.

This New York City bar located on the roof of The McKittrick Hotel is honoring the beloved mathematical constant on March 14 with three gourmet pizzas available for a discounted price of $14 each.

On March 14, this quick-service operator, headquartered in Charlotte, N.C., with over 760 units, will offer each customer three sweet potato pies for $3.14. Bojangles’ is also holding a Pi-themed math quiz on its Twitter account. Participants who answer one question correctly will be entered into a drawing to win gift cards, gear and other prizes.

The fast-casual pizza chain based in Dallas, with over 80 locations, will offer all specialty pies for $3.14 on Pi Day.