Emmaus Post Office 105 N 5th St, Emmaus, PA18049 Located on a quiet residential street, the post office employs five clerks who are on a first-name basis with their…More regular customers. It serves about 500 customers everyday. The office's 19 mail carriers deliver to 8,500 homes and businesses in Emmaus, Upper Milford, Lower Milford and Salisbury. Only disappointment: the post office no longer has a stamp machine, which it had for many years. The first U.S. post office in Emmaus opened in March 1806. It has been at its current location since November 1960.