Member countries
Any member country of the United Nations may become a member of the UPU.
Any non-member country of the United Nations may become a UPU member provided that its request is approved by at least two-thirds of the member countries of the UPU. The UPU has now 192 member countries.
Union expenses are financed jointly by the member countries, through a contribution class system. Upon admission to the Union, new member countries are free to choose one of ten contribution classes ranging from one to 50 units. An additional contribution class of one-half unit is reserved for the least developed countries.