Which amendment grants the right to vote to citizens aged 18 and older?

The 26th Amendment to the United States Constitution specifically addresses voting rights, establishing that citizens who are 18 years of age or older cannot be denied the right to vote based on age. Ratified in 1971, this amendment was largely influenced by the context of the Vietnam War, where many young soldiers who were drafted were unable to vote. Recognizing that if individuals were old enough to serve in the military, they should also have the right to participate in the democratic process, this amendment solidified that principle into law.

In contrast, the other amendments mentioned do not pertain to the voting age. The 24th Amendment addresses the prohibition of poll taxes in federal elections, the 25th Amendment deals with presidential succession and disability, and the 27th Amendment regulates congressional pay changes.