More than a million teachers across the country do not participate in Social Security. There are 12 states that have totally opted out of Social Security. And another 5 states have school districts with mixed coverage (because some districts have opted in, and others have opted out).

Why? When Congress created Social Security in 1935, it excluded state and local workers because of constitutional concerns that the federal government could not tax states and municipalities. In the 1950s, Congress amended the Social Security Act to allow, but not require, state and local governments to enroll their employees. Most states opted in, but more than one third of the country’s teachers live in states that didn’t, resulting in their lack of coverage today.

Read more about why teachers do not have universal access to Social Security at NPR.org and TeacherPensions.org

Note that the map above only reflects Social Security participation for teachers and educators. For a map of participation coverage for state, municipal, and public safety workers see here.