A penny you save is a penny you make, but a penny you spend will buy you a whole cheeseburger this week.

On September 18 — National Cheeseburger Day — Wendy’s customers can get a Jr. Bacon Cheeseburger for 1 cent (with an additional purchase) to celebrate the meeting of beef, bun, and cheese.

Luckily, the offer lasts longer than a day, until September 22. That means people have five days to satisfy their hunger with the change waiting in the bank.

People interested in a burger that costs 89 times less than it did in 1979 can take advantage of the digital offer in the Wendy’s app.

There are a few caveats to this offer, though: The offer is valid for a limited time and is only available at participating Wendy’s in the U.S. You can only redeem the offer in the Wendy’s app or on the website. You must register your account.

Of course, Wendy’s isn’t the only burger joint celebrating National Cheeseburger Day: Burger King is offering members of its loyalty program, Royal Perks, a free cheeseburger on the holiday. The chain is also offering a whole week of other freebies, from mozzarella fries to breakfast sandwiches and more, all included with purchases of $1 or more.

Meanwhile, McDonald’s is selling its double cheeseburgers for 50 cents on the holiday to customers who order through the app. No purchase is required.

In addition to the burger-centric holiday, Wendy’s has a few other fall deals on the agenda. First, rewards members can get a free order of Hot & Crispy Fries (any size) with any in-app purchase every Friday through the end of 2024. Members can also score $1 mini Frosty treats through the end of the month.

Finally, Wendy’s launched the $5 Big Noon Saucy Deal, where customers get a six-pack of Saucy Nuggs in one of seven flavors, a small fries and a small soda for $5. The deal runs throughout football season and is available exclusively in the Wendy’s app.

View all National Cheeseburger Day offers here.