WNS Numbering System

Developed by the Universal Postal Union (UPU) and the World Association for the Development of Philately (WADP), the WADP Numbering System (WNS) was introduced on 1 January 2002 with the aim of creating a database of all authentic postage stamps issued by UPU member countries and territories on or after that date.

Only those postage stamps that, once received by the International Bureau (IB) of the UPU have undergone the process of verification of authenticity and registration will be attributed a WNS number and added to the WNS website.

On the site you can search either by country or topic.

To go to the WNS website, click here.