Work out what kind of collection you have
Philately splits into a few broad types of material, and they behave very differently at auction. A country collection built to a catalogue (GB, Commonwealth, a single European state) is the most straightforward to sell. Thematics — birds, ships, space — are collected widely but sell for far less than their album size suggests. Accumulations of modern mint decimal stamps are usually worth close to their face value as postage, not a premium. Covers and postal history, by contrast, can be worth many times the value of the stamps on them, because the route, the cancellation and the date are the point.
Before you do anything else, separate the collection into those groups. It costs nothing and it is the single thing that most improves the advice you will get.
What actually drives the price
Catalogue value is a starting reference, not a price. Realised prices for common material typically land at a small fraction of catalogue, while genuinely scarce items can exceed it. Four things move the number:
- Condition — centring, perforations, colour and the absence of thins or creases. A well-centred example of a common stamp can be worth many times a poorly centred one.
- Gum — for pre-1950 material, 'unmounted mint' commands a substantial premium over 'mounted mint', and regumming is a serious defect.
- Cancellation — a light, dated, legible postmark on a used stamp adds value; a heavy smudge removes it.
- Rarity of the specific printing — plate flaws, watermark varieties and shade differences separate an ordinary stamp from a scarce one.
When certification is worth the cost
Expert certificates cost money and take weeks, so they are worth getting only where the certificate can move the price by more than it costs. As a rule of thumb, that means items that would be worth a meaningful sum if genuine and undamaged, and where forgery, repair or regumming is a known problem for that issue — classic imperforates, early high values, and anything described as a rare shade or variety.
For everything below that threshold, an accurate, honest description with good photographs does the same job. Buyers of mid-value material are experienced enough to judge from images, and they discount heavily for surprises rather than for disclosed faults.
How the collection gets split into lots
Lotting is where most of the value is won or lost. Items worth roughly a few hundred pounds and up are sold singly, because the bidders who want them will pay properly for them. Below that, material is grouped: by country and period, by thematic run, or as complete albums. Grouping is not a downgrade — a well-described album of a single country attracts dealers and collectors who want depth, and splitting it into hundreds of low-value lots would cost more in handling than it returns.
The mistake to avoid is 'cherry-picking then dumping': pulling out the best twenty items to sell separately and offering the rest as a remainder. The remainder becomes hard to sell, and the total is often lower than a sensibly balanced arrangement of the whole collection.
Preparing the material for sale
Do not soak, clean, re-mount or repair anything. Well-meant tidying destroys more philatelic value than neglect does. Leave stamps on their original covers, leave hinges where they are, and do not attempt to remove old mounts from gum.
What does help: keep the collection dry and out of direct light, transport albums flat rather than upright in a bag, list what you believe is present, and pass on any original purchase receipts, certificates or correspondence. Provenance for a stamp collection is thinner than for a painting, but purchase history from a known dealer still reassures buyers.
Timing, costs and what to expect
Philatelic sales run to a calendar, and specialist sales for a particular country or period will outperform a general sale for the same material. Expect the process from first contact to payment to take a couple of months, not days.
Selling at auction carries a seller commission, and buyers pay a separate buyer's fee on top of the hammer price — Sernelo's schedule is set out on the fees page. Weigh that against the alternative: an outright offer from a dealer is faster and certain, but it is a wholesale price, because the dealer is taking on the work and the risk of finding the eventual collector.