The World Association for the Development of Philately (WADP) and the Universal Postal Union (UPU) jointly conceived and developed the WADP Numbering System - WNS, which was launched on 1 January 2002.

All registered stamps issued by Bulgaria

  1. Bg054.19-80
    Wns Number
    BG054.19
    Country / Post
    Bulgaria
    Date of Issue
    December 12, 2019
    Subject
    25 Years since the establishment of Diplomatic Relations between Republic of Bulgaria and the Sovereign Order of Malta
  2. Bg055.19-80
    Wns Number
    BG055.19
    Country / Post
    Bulgaria
    Date of Issue
    December 17, 2019
    Subject
    70 Years since the establishment of Diplomatic Relations between the Republic of Bulgaria and the People's Republic of China