The voter's oath or affirmation, formerly the freemen's oath, is a citizen's oath or affirmation taken during voter registration in the U.S. state of Vermont. In 2007, the law was amended to make it easier to administer this oath or affirmation; instead of being administered only by notaries public and similar officials, the oath may be administered by nearly anyone, including the applicant. ("Voter's oath or affirmation; how administered" 2007)

The Freemen's Oath was a part of the 1777 Constitution of the Vermont Republic, the first constitution in the Western Hemisphere to grant universal suffrage to all white men and free black men, regardless of property ownership. Several of the American colonies used a Freemen's Oath. Until the early twentieth century all official state commissions and certificates were headed by the words "BY THE FREEMEN OF VERMONT."