Pi Day, held on March 14 each year, is a celebration of the world’s most famous irrational number — and for many, a chance to score discounts on sweet and savory pies. Whether you’re a math enthusiast or just here for the deals, bakeries and restaurants across Chicago offer special promotions for the occasion.
What is Pi Day?
Pi Day was founded in 1988 by physicist Larry Shaw at the Exploratorium, a San Francisco-based science museum. The idea came during a staff retreat, where Shaw linked March 14 (3.14) with the digits of pi (3.14159…) as a way to bring the museum community together, according to the Exploratorium.
The first celebration took place at 1:59 p.m., featuring fruit pies and a tea urn set up by Shaw and his wife. Over the years, the event grew to include a “Pi Shrine,” a circular parade, and a ritual of walking around the shrine 3.14 times while singing “Happy Birthday” to Albert Einstein — whose birthday also falls on March 14.
It wasn’t until 2009 that the U.S. House of Representatives formally recognized Pi Day.
But what exactly is pi, whose symbol is “π”? For starters, this never-ending, non-repeating number is fundamental to the world around us. Pi is the ratio of a circle’s circumference to its diameter, a constant that appears everywhere — from designing bridges to calculating planetary orbits.
The ancient Greek mathematician Archimedes was one of the first to attempt an accurate estimation of pi, but mathematicians today have calculated it to more than 1 trillion decimal places, according to History.com. The word “pi” comes from “perimetros” — a Greek word meaning circumference.
And let’s not forget that March 14 is also Albert Einstein’s birthday. Coincidence? Probably. But it certainly adds to the nerdy charm of the holiday.
Whether you’re in it for the math or just the munchies, some of Chicago’s restaurants and bakeries will serve up π-inspired deals on Friday, March 14. But since Pi Day is essentially the Super Bowl for pie businesses, some skip the discounts and instead roll out more flavors, knowing demand will be high.
Chicago Pi Day Deals
Pizzeria Due
At its River North location, Pizzeria Due is offering a 10-inch, thin crust cheese or pepperoni pizza for $3.14 for dine-in or takeout. Customers ordering individual deep-dish pizzas for takeout can get a second one for $3.14.
First Slice Pie Cafe
All three First Slice locations — Ravenswood, Andersonville and Edgewater — are selling slices of pie for $3.14 on March 14. Customers can also pick up mini pies for $6.28 (equivalent to two slices) or take 15% off whole pies throughout the day.
California Pizza Kitchen
At participating Chicago locations, California Pizza Kitchen is offering a $3.14 pizza to all CPK rewards members. Choices include the Original BBQ Chicken, Pepperoni or Traditional Cheese pizza.
7-Eleven
Convenience store chain 7-Eleven is celebrating Pi Day with $3.14 whole pizzas, quesadillas and chicken tender boxes at participating locations across Chicago.
Burger King
As part of the Pi Day celebration, customers who spend $3.14 or more at Burger King locations throughout Chicago can receive a free Hershey’s chocolate pie.
Blaze Pizza
All Blaze Pizza locations in Chicago are offering 11-inch build-your-own pizzas for $3.14. The deal is available for in-store purchases only.
Gino’s East
At its downtown location on Superior Street, Gino’s East will donate $1 to the Greater Chicago Food Depository for every pizza sold on March 14.
Bang Bang! Pie and Biscuits
Bang Bang Pie Shop, with locations in Logan Square and Ravenswood, is featuring a special Pi Day menu with 15 flavors of sweet and savory pies — including Chocolate Cake Shake, Cherry Crumble, and Chicken Pot Pi(e) —available for pickup on Thursday, March 13, or Friday, March 14.
Bennison’s Bakery
Evanston’s Bennison’s Bakery will offer mini pies for $3.14 all day at its Davis Street location.
Chiya Chai
Both Chiya Chai locations — Logan Square and the Loop — will offer dine-in customers a $3.14 discount on each pie purchase.