For the 40th anniversary of its Book It reading initiative, Pizza Hut is giving away 1 million personal pan pizzas to its customers, celebrating readers of all ages the program has encouraged.

The Book It initiative, which was launched by the restaurant chain in 1984, has worked to ignite a passion for reading among children from pre-K to sixth grade. In the years since it began, Pizza Hut says it has given out more than 1.5 billion pies to young readers.

Now, for the first time, the program will reward readers of all ages.

“The program’s core mission has always been to cultivate a deep, personal connection with reading,” Pizza Hut said in a news release.

In 2019, the Book It initiative was expanded to partner with nonprofit First Book, an organization that provides books at a discount or for free to educators working at Title 1 schools across the United States. According to a new release, the expanded program affected more than 31,000 children in just five years.

The promotion will run throughout the month of October, which also corresponds with National Book Month.

“I’m incredibly proud of what the Book It! program has achieved over the past four decades,” Pizza Hut’s U.S. president Carl Loredo said in a statement. “It’s inspired more than 70 million children to discover the magic of books, helping to build a lifelong love of reading.”

How to get your free pizza from Pizza Hut

Kids, family members and friends can get their free personal pan pizza by using the code “BOOKIT40″ at checkout online or in person using the Pizza Hut app, with any $8 minimum purchase. The code is valid Oct. 1-Oct. 30, or whenever 1 million pies have been given away.

Pizza Hut is also offering the Book It bundle online, which includes two large pizzas and an order of breadsticks, giving a portion of the proceeds from each bundle to the Book It program to inspire more future readers.