Catalogue numbers from various publishers appear in descriptions to aid identification. The general format is catalogue abbreviation followed by catalogue number (SC704, for example).

The numbering systems, including those listed below, remain the copyright of their respective owners.

Numbering system Country Format
John Barefoot Great Britain, Commonwealth BFxxx
Jeffrey Booth Great Britain FDCs BCxxx
Brusden White Australia BWxxx
Connoisseur Great Britain CCxxx
Campbell Paterson New Zealand CPxxx
Collecting Slogan Postmarks Great Britain CSPxxx
Darnell Canada DLxxx
Deegam Great Britain DGxxx
Hibernian Ireland HBxxx
International Stamp & Coin   Brunei, Malaysia, Singapore ISCxxx
Joseph Buttigieg Malta JBxxx
Michel All MIxxx
Murray Payne Commonwealth MPCCxxx
Pierron's Great Britain, Commonwealth   XXXxxx
Ridgewood Great Britain RWxxx
SACC Rhodesias, South Africa SACCxxx
Scott All SCxxx
Stanley Gibbons All SGxxx
Stefan Heijz Falkland Islands, BAT SHxxx
Stoneham Great Britain STxxx
Urch Harris Great Britain, Commonwealth UHxxx
Yang's Hong Kong YGxxx
Yvert et Tellier All YTxxx
Zimbabwean Concise Catalogue  Zimbabwe ZCxxx