At what age are citizens eligible to vote in federal elections?

Citizens are eligible to vote in federal elections at the age of 18. This age requirement is established by the 26th Amendment to the United States Constitution, which was ratified in 1971. The amendment was a response to the argument that those old enough to be drafted for military service should also have the right to vote. As a result, it lowered the voting age from 21 to 18, ensuring that younger citizens could participate in the democratic process.

While other ages mentioned in the choices may have been relevant in different historical contexts or in certain local jurisdictions, 18 is firmly established at the federal level for voting eligibility.