The incident happened on Friday, October 13, at the Post Office on High Street, Edlesborough.
Craig Denning, 40, of Grove Road, Houghton Regis and Steven Magnan, 44, of Hillborough Crescent, Houghton Regis, were charged the following day (October 14) with one count each of robbery.
They appeared at Oxford Magistrates Court on Saturday and are due to appear at Aylesbury Crown Court on November 13.