When was the alcohol age changed to 21?

The drinking age was changed to 21 in 1984, and prior to that, it was 18.

Some states had already raised the drinking age to 21, but it was not until the National Minimum Drinking Age Act was passed that all states were required to do so.

There has been much debate over whether or not the drinking age should be lowered, but as of now, it remains at 21.