This paper analyzes the role of mail art by Argentine mail artists Edgardo Antonio Vigo and Graciela Gutiérrez Marx in subverting Argentine fascism and censorship during the Argentine Dirty War from 1976 to 1983. La Guerra Sucia, or “the Dirty War,” was a seven-year period of right-wing military dictatorship in Argentina, following a coup on 24 March 1976, against the government of President Isabel Perón. The U.S. coordinated with the junta and the Argentine Anticommunist Alliance, or Triple A, and the dictatorship “disappeared” and tortured thousands of so-called enemies of the state. Meanwhile, American and Argentine artists maintained fluid communications, empowering resistance to the regime. Vigo and Marx created the boldest work of Argentine mail art with wide distribution in the form of an “artistamp”, helping spread awareness of the disappearance of Vigo’s son, Abel Luis. By using the postal system as a means of communication with the outside world, Marx and Vigo informed other civilians about the disappeared peoples of Argentina and spread anti-nationalist and anti-government ideology. By taking a closer look at Vigo and Marx’s mail art correspondence with Ohio mail artist Harley Francis, this paper investigates mail art as an understudied aspect of lower-level international political resistance against the Argentine military regime.