Absentee voting allows voters who cannot come to polling places to cast their ballots. A variety of circumstances, including residency abroad, illness, travel or military service, can prevent voters from coming to the polls on Election Day. Absentee ballots permit registered voters to mail in their votes. The Uniformed and Overseas Citizens Absentee Voting Act, a federal law, governs absentee voting in presidential elections. Absentee voting rules for all other elections are set by the states, and vary. Read more about Absentee voting