From Stamps of the World
Chaudfontaine is a municipality (20,935 inhabitants end 2017) located in the province of Liège. It includes Chaudfontaine proper, Beaufays, Embourg, and Vaux-sous-Chèvremont.
The CHAUDFONTAINE post office opened on 29 June 1836. It used a Distribution code 11 then Perception code 138 (in 1850), and 79 with points before 1874. The VAUX-SOUS-CHEVREMONT office opened in 1879, BEAUFAYS in 1905. Postal codes since 1990: 4050-4053