Tucsonans can get tested for HIV today, free of charge, at the Walgreens at 4285 E. Grant Road through 7 p.m.

No documentation is needed, but participants will be asked to fill out a form upon arrival.

The pharmacy chain location is teaming up with the Southern Arizona AIDS Foundation as part of National HIV Testing Day. Walgreens locations in more than 250 cities are holding testing events today, in coordination with Greater Than AIDS, a public information initiative of the Kaiser Family Foundation.

About 13% of the estimated 1.2 million people living in the United States with HIV are not aware that they have it, according to the U.S. Centers for Disease Control and Prevention.