Dunkin' and Krispy Kreme are giving away free doughnuts for national doughnut day

• Friday June 4 2021 is National Doughnut Day.
• Krispy Kreme, Dunkin', and Tim Horton's are all running doughnut discounts for customers.
• DiGiorno also created a limited-edition pizza doughnut.

Friday June 4 is National Doughnut Day, and brands are giving away free treats.

At Krispy Kreme, anyone can get one free doughnut of their choice, no purchase necessary. Customers with proof of COVID-19 vaccination can also get a second glazed doughnut for free.

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"On National Doughnut Day, stop by and enjoy any doughnut you want on us. And if you're helping us get past this pandemic by getting your COVID-19 vaccine, then THANK YOU and have a second doughnut on us," CMO Dave Skena said in a statement.

Krispy Kreme says it has already given away more than 1.5 million free doughnuts since launching the program in March, with plans to give out thousands more through the rest of the year.

Dunkin' will also give out free doughnuts with the purchase of a beverage, the company said. To celebrate, Dunkin' also launched a National Doughnut Day merch collection with tote bags, tee shirts, and sweatshirts.

Tim Horton's is selling doughnuts to rewards members for only 50 cents with any purchase over 50 cents, and the deal lasts through June 15.

Finally, frozen pizza seller DiGiorno is giving fans the chance to try a combination pizza and doughnut, or DiGiornut.

-DiGiorno (@DiGiorno) June 4, 2021

Anyone 18 years old or older can enter online by the end of National Doughnut Day for the chance to try the unusual offering.

Do you have a story to share about a retail or restaurant chain? Email this reporter at mmeisenzahl@businessinsider.com.