A stamp catalog is a catalog of postage stamp types. Although basically just a list of descriptions and prices, in practice the catalog is an essential tool of stamp collecting.

Originally catalogs were just dealers' price lists, and in some cases, such as Stanley Gibbons, that is still one of their functions. Over time, as philately developed, catalogs tended to accumulate additional supporting details about the stamps, such as dates of issue, color variations, and so forth. As their use by collectors became widespread, the catalogs came to define what was and was not a legitimate stamp, since collectors would avoid stamps not described in their catalog.

There are only a handful of catalogs with worldwide coverage:

  • Michel catalog
  • Minkus catalog
  • Stanley Gibbons catalog
  • Scott catalog

These are large undertakings, since there are thousands of new stamps to describe each year, and the prices of all stamps may go up or down. (In the case of publisher that are not dealers, the prices are estimated by collection of data from dealers and auctions.)

In addition, the catalog publishers usually put out specialized volumes with additional details, generally by nationality; Michel has a specialized German catalog, Scott a specialized US, and so forth.

Notable country catalogs:

  • Anfils catalog (Spain)
  • Ma catalog (China)
  • Yang catalog (China)
  • Zumstein catalog (Switzerland)

Building on this idea, many specialized catalogs have been published, for instance to list and value different kind of postmarks used in a particular country during a single era.