Catalogue value is not a price
Stanley Gibbons catalogues list a value for every British stamp. It is a retail price for a fine example from a dealer’s stock, and the trade treats it as a unit of account rather than a sum anyone pays.
Common material changes hands at a small percentage of catalogue, and only scarce stamps in fine condition approach it. An album that “catalogues at £5,000” and sells for £400 is the normal outcome, not a swindle.
| Material | What it realises against catalogue |
|---|---|
| Common used stamps in quantity, mixed condition | 1 to 3 percent |
| General album material, worldwide, no strong country | 2 to 5 percent |
| Good used Victorian and Edwardian, fine condition | 10 to 25 percent |
| Unmounted mint before 1953 | 25 to 40 percent |
| Scarce classics, fine, with a certificate | 50 percent and above |
| Modern mint after 1971 | Priced as postage, not against catalogue |
Those ratios are the reason two honest people quote wildly different figures for the same album. One is reading the catalogue and one is reading the market.
What the SG number means
Every British stamp has a Stanley Gibbons number, written as SG 1 for the Penny Black and running upward. A dealer’s list of “SG 43, fine used, £12” is naming one exact stamp: a specific value, watermark, perforation and printing.
The number matters because a difference invisible to a general reader separates a £2 stamp from a £200 one. Two stamps of the same design and colour can be different SG numbers because of the watermark in the paper, the perforation gauge at the edge, or the plate they came from.
This is why an untrained valuation of an album is worth so little, and why the specialist turning the pages is looking at the paper rather than the picture.
What a specialist does with an album
They turn the pages quickly and stop rarely. They are looking for the small number of stamps that carry the value: early issues, high values, unmounted mint sets from before the 1950s, errors and varieties, and rarities of colour or watermark. Everything else is bulk and is priced by the album, the box or the kilogram.
| Sells individually | Sells as bulk |
|---|---|
| Penny Blacks, early Penny Reds, 2d Blues | Victorian and Edwardian low values in quantity |
| High values: £1 and £5 stamps of any reign | Commemorative sets from the 1960s onwards |
| Unmounted mint sets before 1953 | Mounted mint and used sets after 1953 |
| Errors, inverted watermarks, missing colours | Presentation packs and year books |
| Rare Commonwealth and colonial issues | Worldwide “one of each country” albums |
| Postal history: covers with routes, rates or scarce postmarks | Loose stamps off paper, sorted by country |
Mint, unmounted and used
A mint stamp has never been used. Unmounted mint means the gum is untouched by a hinge. Mounted mint means a hinge has been stuck to the gum, and the price drops, sharply for twentieth-century issues. Used means postmarked.
For Victorian stamps a fine used copy is worth more than a mounted mint one in many issues, since so few survived unused. For stamps from the 1930s onwards unmounted mint is what counts, and the same stamp hinged is worth a third of it.
Never try to remove a hinge. The gum comes with it and the stamp becomes a used-value copy with no cancel.
Condition, and what ruins it
Centering, perforations, gum and freshness of colour decide condition. Each of these costs money.
| Fault | What it does |
|---|---|
| Pulled or short perforations | Takes 50 to 80 percent off a modern stamp |
| Thin, where paper is missing from the back | Halves the price at best |
| Crease or bend | Substantial, and it shows in raking light |
| Toning or foxing from a damp loft | Ruins a whole album at once |
| Fading from sunlight on a shelf | Permanent, and it kills colour-sensitive issues |
| Poor centering | A third off a stamp that would otherwise be fine |
| Hinge remnant on gum | Mounted mint pricing rather than unmounted |
Store the album somewhere dry and dark until it is sold, and do not remove stamps from it. An album that has spent thirty years in a loft is worth a fraction of the same collection kept indoors, and nothing can be done about it afterwards.
Decimal stamps and postage
Mint decimal stamps from 1971 onwards are bought by the trade for use as postage, at a discount to face value of roughly a fifth to a third. A box of presentation packs is worth its face value less that discount, and no more.
Add up the face value on the covers of the packs before asking anyone for a price. It is the one part of a collection an executor can value without help, and it is the largest single number in most estates’ stamp holdings.
First day covers are covered in their own guide.
What bulk material makes
The bottom of the market has its own units. Kiloware is stamps on paper sold by weight, and it makes a few pounds a kilogram for modern British material. A shoebox of loose common stamps is a single lot. A run of identical albums from a club or a dealer’s stock is priced by the shelf.
None of this is worth sorting by hand. An hour spent separating common stamps earns less than the minimum wage, and the sorting can damage the few stamps that mattered.
How to photograph a collection for an opinion
A valuer working from photographs needs five things, and nothing else helps.
- The spines of every album together, so the extent is clear.
- The first four pages of each album, which show the earliest material.
- Any page that looks early, dense or unusual, photographed square and in daylight.
- Close-ups of any stamp that looks like a Penny Black, a high value or a large classic.
- The backs of the presentation packs, showing the face values.
Photograph flat, in daylight, without flash, with the page filling the frame. Do not use a phone’s document scanner, which crops and sharpens in ways that hide faults.
How to sell
Ask two auction houses with stamp departments for a free opinion, using those photographs. The valuation form covers one of the two. They will say whether the collection is worth individual lotting, a single lot, or a dealer’s offer.
| Route | Suits | Timing |
|---|---|---|
| Specialist stamp auction, lotted | Early GB, classics, strong single countries, above £1,000 | Three to five months |
| Specialist auction, single lot | Mixed albums with something good in them | Two to three months |
| General saleroom | Boxes of albums with nothing early | Weeks |
| Dealer’s offer | Anything under a few hundred pounds, or a quick sale | Days |
For anything under a few hundred pounds a dealer’s offer is quicker and the difference is small. For collections with early material, auction with the good stamps lotted separately is where the value is realised. The auctions guide explains the charges, and where to sell a stamp collection works through what each of those four buyers pays and when.
