Collecting · Specialist
Stamp Errors and Varieties: A Collector's Guide
An error is a stamp that went wrong in production, such as a missing colour, an inverted centre, or a wrong shade, while a variety is a recognised, consistent difference between printings, such as a particular watermark or perforation. Genuine errors can be rare and highly valuable, since few escape, but because they are so prized, authentication is essential: many "errors" are fakes, damage or ordinary varieties mistaken for something rarer.
At a glance
Errors, varieties and flaws
It helps to separate three things often confused. An error is a genuine production mistake that should not have left the printer: a missing colour, an inverted part of the design, a wrong shade, an imperforate stamp among perforated ones. A variety is a recognised, consistent difference between printings, a particular watermark, perforation or plate state, catalogued and collected as a distinct stamp.
A flaw is a minor, often one-off blemish on a single stamp. Errors and varieties are collectable; a mere flaw usually is not. Our glossary explains the terms.
Famous errors and varieties
- Inverted centres. Where a two-part design has the centre printed upside down, as in the famous Inverted Jenny of the United States. Our most valuable world stamps guide features it.
- Missing colours. Where a colour failed to print, leaving part of the design blank.
- Wrong shades and colours. Such as the British 1935 Prussian Blue, a scarce colour error of the Silver Jubilee, covered in our King George V value guide.
- Imperforate errors. Stamps that escaped without their perforations. Varieties, by contrast, are the watermark, perforation and plate differences the specialist studies, which our guides to watermarks and perforations explain.
Prized, and heavily faked
Authenticate everything
Genuine errors can be among the most valuable stamps in the world, which is exactly why so many "errors" are fakes, damage or ordinary varieties. Value rests entirely on authenticity, never assume, and never buy or sell a valuable error on hope.
Why authentication is essential
Never assume an error is genuine
Here is the heart of the matter, and the warning. Because genuine errors are so valuable, they are heavily faked, and many supposed errors are nothing of the kind: a colour can fade rather than be missing, perforations can be trimmed to fake an imperforate, damage can mimic a flaw, and ordinary varieties are often mistaken for rarities. For any error you believe to be valuable, expert authentication and a certificate from a recognised authority are essential, never assume, and never buy or sell a valuable "error" on hope. Our guide to spotting a fake or repaired stamp explains the warning signs, and our quality and grading standards explain how we describe every item honestly.
How to value errors and varieties
The value of a genuine error or variety depends on how dramatic and how rare it is, how many are known, its condition, and collector demand, and the great errors can be worth very large sums. But value rests entirely on authenticity: an unverified "error" is worth little, and a faked one nothing. Our guides to what affects a stamp's value and how to get a valuation explain the principles, and we are always glad to give an honest opinion before you assume value.
Collecting errors and varieties
Errors and varieties are a fascinating field, from affordable minor varieties to the great rarities of philately. They reward knowledge and a careful eye, and above all a healthy scepticism, since the field attracts fakes. Collected with proper authentication, they are among the most exciting stamps there are. We are glad to help, each item honestly described and photographed; browse our stock, or ask us what is available.
Frequently asked questions
A stamp that went wrong in production and should not have left the printer, such as a missing colour, an inverted centre, a wrong shade or a missing perforation. Genuine errors can be rare and valuable.
An error is a production mistake, while a variety is a recognised, consistent difference between printings, such as a particular watermark or perforation. Both are collected, but they are different things.
Genuine errors can be highly valuable, since few escape, but value rests entirely on authenticity. Many "errors" are fakes, damage or ordinary varieties, so expert authentication is essential.
Only by expert authentication and a certificate from a recognised authority. Never assume an error is genuine, since colours fade, perforations are trimmed, and varieties are mistaken for rarities.
Fascinating, but authenticate everything
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Founder and stamp dealerLast updated June 2026