Compared
Original Gum, Hinged or Never Hinged: A Guide to Gum
For a mint stamp, the state of the gum on the back matters greatly to its value. The grades run from mint never hinged (perfect, undisturbed original gum) through lightly hinged and more heavily hinged (where a hinge has left a mark) to unused without gum (no gum at all). Never hinged is worth most, all else being equal. Beware regumming, where fresh gum is added to imitate a finer grade.
| Grade | The gum |
|---|---|
| Mint never hinged (MNH/UM) | Perfect, undisturbed original gum |
| Lightly hinged (MVLH/MLH) | A small, faint hinge mark |
| Hinged (MH) | A more obvious hinge mark |
| Unused, no gum | No gum at all |
| Regummed (beware) | Fresh gum added later, a fault |
Why gum matters
To a collector of mint stamps, the gum on the back is part of the stamp's condition, and a major part of its value. The ideal is original gum, the gum applied when the stamp was made, undisturbed and intact. Anything that disturbs it, above all a hinge, reduces the grade and the value.
This is why how a stamp has been mounted matters so much, and why mounts, which never touch the gum, are preferred to hinges for mint stamps, as our guide to hinges versus mounts explains.
The grades of gum
- Mint never hinged (MNH), also unmounted mint (UM). Perfect, full original gum, never mounted on a hinge, the finest grade. Our guide to MNH explains.
- Mint very lightly hinged (MVLH) or mounted (MLH). A small, faint hinge mark on otherwise good gum. Our guide to MVLH explains.
- Mounted mint / hinged (MH). A more obvious hinge mark or disturbance to the gum.
- Unused, no gum. A stamp with no gum at all, whether never gummed or with gum removed. Worth less than a gummed example, but honestly so. All of these are honest states, openly described. The grade simply records how the gum stands.
The warning: regumming
The one state that is not honest
There is one state that is not honest, and you should know of it: regumming. This is the practice of applying fresh gum to the back of a stamp, to make a no-gum or lightly hinged stamp appear never hinged, and so more valuable. It is a form of faking, and a costly trap, since a regummed stamp is worth no more than its true state, and to a knowing buyer rather less. Suspiciously perfect, even gum on an older stamp can be a sign. Our guides to spotting a fake or repaired stamp and how to tell if a stamp is mint or used explain how to be careful, and we describe the gum of every stamp honestly.
What it means for value
The gum grade can make a real difference to a mint stamp's value, sometimes a large one, with never hinged commanding a premium over hinged, and hinged over no gum, all else being equal. How much depends on the stamp and how fussy its collectors are about gum. For used stamps, of course, gum does not arise, since they have been through the post. The key, as always, is honest description: a stamp openly graded for its gum can be bought and sold with confidence, as our guide to condition and value explains.
Frequently asked questions
That a mint stamp has its full original gum, perfect and undisturbed, and has never been mounted on a hinge. It is the finest gum grade and worth most, all else being equal. Our MNH guide explains.
A never hinged stamp has perfect, undisturbed gum; a hinged stamp has a mark or disturbance where a hinge was attached. Never hinged is worth more, since the gum is original and intact.
Applying fresh gum to a stamp to make it appear a finer grade than it is. It is a form of faking; a regummed stamp is worth no more than its true state, and less to a knowing buyer. Be wary of suspiciously perfect gum.
For mint stamps, greatly. Never hinged commands a premium over hinged, and hinged over no gum, all else being equal. For used stamps, gum does not arise.
Never hinged, hinged, or no gum
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Founder and stamp dealerLast updated June 2026