Which amendment addresses the voting age in the United States?

The 26th Amendment to the United States Constitution specifically addresses the voting age, lowering it from 21 to 18 years. This amendment was ratified in 1971 primarily in response to the arguments presented during the Vietnam War, where young men were being drafted to fight yet were not allowed to vote. By establishing 18 as the minimum voting age, the amendment recognized the rights of younger citizens to participate in the democratic process, ensuring that those who are considered adults in other respects—such as military service—would also have a voice in how their government is run.

Looking at the other amendments mentioned, the 16th Amendment allows Congress to levy an income tax, the 19th Amendment grants women the right to vote, and the 15th Amendment prohibits voter discrimination based on race. None of these address age specifically, making the 26th Amendment the clear choice regarding the voting age in the U.S.