According to the CDC, about a third of the United States population is fully vaccinated. (Here's how to get a COVID-19 vaccine if you haven't yet.) Vaccines are rolling out for all people age 16 and up. And the good news keeps on coming: Krispy Kreme announced a sweet incentive earlier this spring to help boost vaccinations: free doughnuts.

The doughnut-maker is specifically offering one free Original Glazed doughnut to "anyone who shows their COVID-19 Vaccination Record Card" at "participating US locations." The promotion began in March and runs through Dec. 31. It will allow for "one redemption per guest per day" so you could, in theory, get a free doughnut every day for the rest of the year -- if you're vaccinated. 

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How do you get a free Krispy Kreme doughnut a day if you're vaccinated?

To qualify, you will need to present your COVID-19 vaccination card. It will need to show that you have had at least one of the two shots of the Moderna or Pfizer vaccines or the single-shot Johnson & Johnson vaccine. 

Wearing your "I'm vaccinated" sticker will not count. The company adds on its website that employees will not document or take photos of your vaccine card since it "contains personal information." 

You will need to head into a Krispy Kreme store or drive-thru to get the deal, with the company noting that it is not making the free doughnuts available to those ordering online or via delivery apps.  

You can still get a free Krispy Kreme doughnut even if you don't get the vaccine

Those who decide not to get the vaccine can also get free doughnuts, though Krispy Kreme's offer there is more limited.

"We understand that choosing to receive the COVID-19 vaccine is a highly personal decision," the company said on its website. It adds that if you decide not to get the vaccine you can still get a free Original Glazed doughnut and medium brewed coffee on Mondays, "to get your week off to a good start." 

The offer for people who are not vaccinated runs each Monday through May 24.