A definitive stamp is issued primarily for the payment of ordinary postal rates and is normally printed as required rather than in a predetermined limited quantity. As stocks are used, further printings may be produced according to postal demand. The primary purpose of definitive stamps is therefore to meet the everyday needs of the postal service, which distinguishes them most clearly from commemorative issues.

During the early decades of postage stamps, virtually all issues were produced for ordinary postal use. Hungary’s first commemorative stamp issue appeared in 1916 for the coronation of Charles IV.

Definitive stamps are usually smaller and visually simpler than commemoratives. The different denominations in a definitive series generally share a consistent design and were historically often printed in a single colour. This was economical, while clearly differentiated colours also helped postal users and staff recognise the various denominations more quickly.

The subjects of definitive series are usually simpler, although their design can still be highly artistic. The individual denominations normally resemble one another much more closely than those in commemorative sets.

Because definitive stamps are often printed in very large quantities and over long periods, they can provide a rich field for collecting plate flaws, colour shades, perforation varieties and other production differences.

As traditional letter mail and stamp usage have declined, the role of long-running definitive series has also diminished. In recent decades, a growing share of everyday postal needs has been covered by commemorative and thematic issues as well.