It's the question every inherited album raises. The honest answer is that most stamps are worth very little, because they were printed in millions and kept by millions of people. A few are worth a lot, and the difference comes down to a handful of factors you can check yourself.

What makes a stamp valuable

  1. Rarity. How many were printed, and how many survive. Short-lived issues, stamps from small territories, and stamps withdrawn soon after release tend to be scarce.
  2. Demand. A scarce stamp from a country few people collect can be worth less than a common stamp from a very popular country. Great Britain, the USA, Germany, China and the British Commonwealth have large collector bases.
  3. Condition. Centering, fresh colour, full perforations and undamaged gum can multiply the value of the same stamp. See mint vs used stamps and condition grades.
  4. Errors and varieties. Inverted centres, missing colours, imperforate sheets and wrong watermarks are the headline-makers of philately.
  5. Postal history. A stamp on its original envelope, with interesting postmarks, routes or censor marks, can be worth far more than the stamp alone.

Catalogue value vs what you'll be paid

Catalogues such as Scott, Stanley Gibbons and Michel list a value for each stamp. Treat it as a reference point, not a price:

  • Common stamps often sell for a small fraction of catalogue value. Catalogues also apply a minimum value that mostly reflects a dealer's cost of handling a stamp.
  • Dealers buying a collection have to resell it, so their offers sit well below retail.
  • Scarce stamps in top condition can sell above catalogue value.

Signs a collection deserves a closer look

  • Stamps from before about 1900, especially unused ones
  • Complete sets, or whole sheets, from older issues
  • Old envelopes with stamps still attached
  • Anything that looks different from its neighbours: an odd colour, a missing perforation edge, an upside-down element
  • Stamps in stock books or glassine envelopes kept by a serious collector, rather than a child's album

Signs it's probably a modest collection

  • Mostly modern, used stamps soaked off everyday mail
  • Mass-market packets bought from a shop, often with a lot of colourful "topical" stamps
  • Stamps glued, taped or heavily hinged into a beginner's album

What to do next

  1. Sort stamps by country and rough date.
  2. Identify the most promising ones (see how to identify a postage stamp).
  3. Check catalogue values, and look at completed sales, not asking prices, on auction sites.
  4. For anything that could be significant, get an expert certificate from a recognised society before selling. Valuable stamps are often faked or repaired.

AI Stamp gives an estimated value range for each stamp you scan. Use it to sort the likely treasures from the bulk before you spend time on research or expert opinions.