Where is the plate number on a stamp?

Either engraved within the design, as on the perforated Penny Red, or printed in the sheet margin, where it survives only on marginal pieces.

What is the Penny Red Plate 77?

A famous rarity. Plate 77 was found defective and meant to be destroyed, but a few stamps from it survive and are among the most valuable British stamps.

How do you find the plate of a Penny Black?

The Penny Black has no printed plate number, so it is "plated" by studying its check letters and the features unique to each plate.

What is the difference between a plate number and a cylinder number?

A plate number identifies the plate on line-engraved or typographed stamps; a cylinder number does the same for photogravure-printed stamps.

Glossary

What Is a Plate Number?

A plate number is a number that identifies the specific printing plate used to produce a stamp. It may be engraved within the stamp's design or printed in the sheet margin, and on some classic stamps, such as the Penny Black, it carries no printed number at all and must be worked out by studying the stamp itself. Plate numbers matter because different plates vary in scarcity and value, and collecting a stamp by completing all its plates is a popular pursuit.

Identifies the printing plate

In the design or the margin

Key to specialists

Penny Red plates

Engraved in the design

At a glance

MeansThe number of the printing plate used

FoundIn the stamp's design, or in the sheet margin

On some classicsIdentified by study (plating), not printed

Why it mattersPlates vary in scarcity and value

Famous exampleThe Penny Red Plate 77

Related termsCylinder number, control

What a plate number is

Stamps are printed from plates, and during a long-running issue a single design may be printed from many plates as each wears out and is replaced. Each plate is numbered, and that number is the plate number.

Knowing the plate number ties a stamp to a particular plate, and so to a particular point in the printing of an issue. For the specialist, that is the difference between a stamp and a stamp with a story.

Where you find a plate number

In the design. On some line-engraved issues, the plate number is engraved small within the design itself, so it appears on every stamp from that plate and can be read on a single stamp.
In the sheet margin. On many issues, the plate number is printed only in the margin (the selvedge), so it survives only on marginal stamps and blocks, not on a stamp from the centre of the sheet.

A plate number may be engraved within the side design of a line-engraved stamp, or printed in the sheet margin of a corner block.

The Penny Red and the Penny Black

The two most famous British stamps show the two approaches perfectly, which is part of why they are so absorbing to collect.

The perforated Penny Red of 1858 to 1879, known as the "Penny Red plates", carries its plate number engraved in the design, worked into the lattice on each side of the stamp. Because of this, every stamp can be assigned to its plate, and collectors gather the issue plate by plate. The plates run from 71 to 225, though not all were issued.

The Penny Black of 1840 is different. It carries no printed plate number at all. Instead, specialists "plate" it, identifying which of its plates a stamp came from by studying its check letters and the tiny features unique to each plate. It is one of the most rewarding studies in all of philately, and a skill in its own right.

Why plate numbers matter to value

Different plates were used for different lengths of time, and some carried flaws, so certain plates are far scarcer than others. Scarce plates carry a premium, and completing a full plate run is a genuine achievement.

The Penny Red Plate 77

The most celebrated example is the Penny Red Plate 77. The plate was found to be defective and was supposed to be destroyed, yet a handful of stamps from it survive. They are among the most valuable of all British stamps, and a reminder of how much a single plate number can matter.

For most stamps the differences between plates are modest, but the principle is the same: the plate number is part of what a stamp is, and sometimes it is the most valuable part.

Plate number identifies the plate on line-engraved and typographed stamps.
Cylinder number is the equivalent on photogravure-printed stamps, such as many modern British issues, and is found in the margin.
Control is a letter and number in the margin of some early twentieth-century British stamps, indicating the printing.

Each is explained in our glossary.

How we record plate numbers

Where a stamp carries a plate number, or comes from a notable plate, we identify it and note it in the listing, with high-resolution images so you can see it for yourself. For the line-engraved Great Britain stamps that are our particular specialism, this detail is often the whole point, and we make a point of recording it. You can read more on our quality and grading standards page, or about our background on the meet the expert page.