Postage stamps are used as evidence of payment of postage for services to be performed by the post. Depending on the purpose of the issue, postage stamps are divided into common stamps and special – commemorative stamps issued to commemorate important events or their anniversaries (historical, social, cultural) and particularly merited or distinguished persons, as well as to honour political, philatelist or other anniversaries and events. Such stamps are usually issued as one short series, as a miniature sheet or with a tag.
In Poland, Poczta Polska SA is the sole the sole issuer of postage stamps. The stamps are issued on the basis of an annually prepared plan whose final version for the subsequent year is issued in the form of a decision of the Minister of Administration and Digitalisation. The plan provides for the themes, printing techniques, issue dates and number of stamps in the given series. Designs to be included in the plan are approved by a committee composed of the employees of Poczta Polska SA. A decision on the number of stamps issued is made by the President of the Management Board of Poczta Polska SA. A stamp design may be submitted to the committee by both an institution and an individual.
The majority of issued stamps are common stamps. They are printed in multi-million numerously repeated series intended for common use in everyday correspondence. Commemorative stamps, sheets and miniature sheets connected with specific events are a separate category. They are issued only once, usually in low volumes. Such stamps are interesting for philatelists.
PWPW has been the producer of postage stamps for Poczta Polska for many years now. The annual issue is over one billion units. The firm's portfolio includes scented stamps, triangular stamps, stamps with dry pressing, stamps printed with the use of non-standard inks as well as pre-prints for making personalised stamps.
Stamps produced by PWPW are divided into two groups:
Most frequently, printed stamps have the following sizes: 43 mm x 31.25 mm, 39.5 mm x 31.25mm, 51 mm x 31.25 mm, and in the case of miniature sheets - 90 mm x 70 mm. The printed stamps may have various shapes (other than rectangular shape), for example, square, triangular or circular. Stamps may also be printed on self-adhesive substrate.
The exceptional quality of this group of products is certified by the fact that PWPW has numerously received awards and distinctions for the best printed stamp, awarded at conferences organised by the Association of Governmental Producers of Postage Stamps. In 2014, at such event held in Beijing, the "900th anniversary of Gallus Anonymus Chronicles" stamp was awarded the first prize in the sector of steel engraving.
While producing postage stamps PWPW uses various printing techniques, such as rotogravure, offset, screen printing, steel engraving and dry pressing.
The following security features are used in the production of postage stamps: