The promotion is capped at 10,000 offers. It is not available in Alabama, California, or Texas. And technically, the prize isn't a beer, but a "$5 virtual debit card" to be used on beer.
Back in March 2021, doughnut chain Krispy Kreme pioneered the concept of rewarding people who received a COVID-19 vaccine with free samples of their product. In April 2021, beer conglomerate Anheuser-Busch launched a similar initiative as part of their "Reunited with Buds" campaign. The premise, announced in an April 15 television ad, is that Budweiser will cover the cost of a beer if you prove that you are vaccinated:
The promotion is real, although the prize is not actually a free beer. Instead, the first 10,000 people (excluding those who live in Alabama, California, or Texas) who upload proof of vaccination to a Budweiser online rewards program from April 15 to May 16, 2021, will receive a "$5 virtual debit card" that can be used to purchase a beer.
According to the terms of the promotion, "proof of vaccination" can come in the form of:
Uploading a picture of your “I Got Vaccinated” sticker;
Uploading a picture of your band aid; or,
Uploading a photo (selfie) showing us that you have been vaccinated at a vaccination location.
Because the promotion is real, the claim is true.