Pizza Hut is giving away free pizza to anyone with an old BOOK IT! reading button

Participation requires no purchase, and buttons are accepted regardless of which year they were issued. The promotion ends at 11 p.m. CT or whenever supplies run out, the company said.

The one-day giveaway is the opening move in a summer-long platform Pizza Hut is calling Hut Originals, which the Yum Brands $YUM chain said is built around food, experiences, and customers connected to the brand's history. "BOOK IT! continues to be one of the most beloved and talked-about programs tied to the brand," Chief Marketing Officer Melissa Friebe said in a statement.

A separate BOOK IT! Summer of Stories initiative runs through the end of August and is available to students from pre-kindergarten through sixth grade. To enroll, parents download the free BOOK IT! app — available through the App Store or Google $GOOGL Play — and establish monthly reading targets; hitting those targets earns the child a free Personal Pan Pizza, the company said.

For the first time, Pizza Hut is pairing the program with a Box Tops for Education partnership with General Mills $GIS. Scanning a receipt from the BOOK IT! Family Meal — priced at $14.99 and consisting of one medium one-topping pizza alongside two one-topping Personal Pan Pizzas — in the Box Tops app generates cash contributions to eligible schools. The company also said a share of proceeds from each meal sale goes back into the BOOK IT! program to fund literacy work.

The BOOK IT! program dates to 1984 and rewards students with a free personal pan pizza for meeting a monthly reading target. According to People, the concept took shape in part through conversations about President Ronald Reagan's public push for literacy, with and Bud Gates, a marketing executive at the company, eventually landing on pizza rewards after reflecting on what might spark a genuine love of reading in his own child.

The Hut Originals platform also includes the recently launched Crispy Parm Pan Pizza and promises fan-favorite menu items at throwback prices, merchandise partnerships, and Pizza Hut Classic location experiences throughout the summer, the company said. As part of the same nostalgia push, close to 155 locations have been converted into Pizza Hut Classic sites, where period details from the 1980s and 1990s — among them Tiffany-style lamps, arcade games, and checkered tablecloths — recreate the chain's vintage dine-in atmosphere.

Pizza Hut is currently the subject of a potential sale, with parent company Yum Brands in exclusive talks with private equity firm LongRange Capital, according to Reuters.