How to Soak, Sort, and Store Stamps

Most collections begin with a pile of envelope corners: a shoebox from a relative, a bag of kiloware, or the stamps you have been tearing off your own post. Turning that pile into a collection takes three jobs — getting the stamps off the paper, working out what you have, and putting them somewhere safe. None of it needs special equipment, but each step has a way of going wrong that is worth knowing about before you fill the bowl.

First, Decide Whether to Soak at All

Soaking is irreversible, so sort before you wet anything. Set aside:

• Whole envelopes worth keeping. A clear cancellation, an unusual route, a special postmark or an old date can make the complete cover more interesting — and more valuable — than the loose stamp. If in doubt, keep it whole. You can always soak later; you can never un-soak.
• Stamps on coloured paper. Red and green envelopes (Christmas cards are the usual culprits) bleed dye into the water and stain every stamp in the bowl. Soak them separately, in cold water, or not at all.
• Stamps with fugitive inks. Some issues were printed in inks designed to run when wet, to stop people washing off cancellations and reusing them. Netherlands Indies issues and many British and colonial stamps in green and purple from the late Victorian and Edwardian periods are the well-known cases. Check a catalogue before soaking anything old.
• Anything with a purple or handwritten cancel. Hand-stamp and manuscript inks often run even when the stamp’s own ink is stable.
• Modern self-adhesives. These get their own section below, and a full guide: How to Remove Self-Adhesive Stamps from Paper.

What remains — ordinary water-gummed used stamps on white or buff paper — is what soaking was made for.

How to Soak Stamps

You need a shallow bowl, lukewarm water, stamp tongs, and something absorbent to dry on.

1. Trim the paper. Cut around each stamp leaving a few millimetres of envelope. Never cut into the perforations.
2. Fill a shallow bowl with a few centimetres of lukewarm water. Hot water works faster but is far more likely to make inks and envelope dyes run. Cool water is the safest choice for anything you are unsure about.
3. Float the stamps face up, a small batch at a time — somewhere between ten and fifty. An overcrowded bowl leaves stamps stuck to each other and sitting in dissolved gum.
4. Wait. Most stamps let go within ten to twenty minutes; some need an hour. A stamp is ready when it slides off the paper with no resistance. If you have to pull, it is not ready — and pulling is how you create a thin.
5. Rinse the back gently in clean water to remove the last of the gum. Leftover gum is what makes stamps curl and stick to the drying paper.
6. Change the water every two or three batches. Cloudy water is gum solution, and it will redeposit on the next batch.

Wet stamps are at their weakest. Handle them with tongs, by the body of the stamp rather than a corner, and never stack them.

Drying and Flattening

Lay the rinsed stamps face down on plain white kitchen paper or blotting paper, not touching each other, and let the surface water go for a few minutes. Then cover them with a second sheet and put a heavy book on top. Leave them overnight.

Two things to avoid:

• Heat. Hairdryers, radiators and sunny windowsills dry stamps quickly and curl them badly.
• Printed or patterned paper. Newspaper ink and the embossed pattern on some kitchen towels both transfer to damp stamps. Plain and smooth is what you want.

If you soak regularly, a purpose-made drying book — alternating sheets of blotting paper and smooth release paper — is a small expense that produces noticeably flatter stamps. A stamp that still curls after drying usually has gum left on it; re-soak it briefly, rinse properly and press again.

The Self-Adhesive Problem

Here the tidy textbook method stops working. Most stamps issued today are self-adhesive, and many of them use pressure-sensitive glues that water does not dissolve. The American Philatelic Society notes that many United States self-adhesives issued from 2004 onwards will not soak easily, if at all.

Collectors’ own reports on hobby forums are consistent on this, and worth hearing before you sacrifice a batch:

• It depends heavily on the country. One collector who tested widely found that self-adhesives from Germany, Australia, Switzerland, France, Spain and Portugal came away cleanly given extra time, while those from the United States and Brazil were damaged, and Russian, Italian and British ones were troublesome. Another reported Italian stamps releasing after half an hour but keeping a tacky residue, and Russian ones not budging after an hour.
• Recent US stamps defeat plain water. Several people describe destroying stamps trying, or finding them still firmly attached after long soaks in water and even rubbing alcohol.
• Patience beats temperature. A collector who soaks in very cold water and simply waits — up to an hour — reports losing only a handful of stamps in every hundred, mostly ones on poor-quality paper. Others who reached for hot water to speed things up watched colours fade.
• Solvents work, with caveats. The method that circulates most among US collectors uses a few drops of a heptane-based solvent (sold as Bestine) or a non-aerosol citrus-based adhesive remover applied to the paper side, after which the stamp peels away; a dusting of talc on the back then kills the remaining tack. Others use high-proof ethanol or a label-remover pen. All of these are flammable, need ventilation, and should be tried on worthless duplicates first. Results on thick card are reported to be poor.
• Many have simply stopped. A common view among experienced collectors is that soaking modern self-adhesives is no longer worth the mess: they trim the paper neatly, leaving an even margin of a few millimetres, and collect the stamp “on piece”.

That last option is the one to start with. A neatly trimmed self-adhesive on paper is a perfectly respectable way to collect a modern used stamp, it preserves the cancellation, and it risks nothing. When you are ready to experiment, How to Remove Self-Adhesive Stamps from Paper walks through each method step by step.

Sorting What You Have

Once everything is dry and flat, sort in passes rather than trying to do it all at once:

1. By country. This is the natural first cut, and where a catalogue or an online identifier earns its keep.
2. Within a country, by period or set, by theme (birds, ships, space), or by type — definitives, commemoratives, airmail, postage due, revenue stamps.
3. By condition. Pull out stamps with tears, heavy creases, missing perforations or thins. Unless a damaged stamp is scarce or hard to replace, it does not belong in the album. Our stamp grading guide explains what to look for.
4. Duplicates. Keep the best copy — well centred, with a light, clean cancel — and put the rest aside for swapping.

Sorting is never finished, and there is no correct scheme. Many collectors change their minds about what they collect several times; the sort simply follows.

While you work, keep sorted groups in glassine envelopes labelled in pencil, or in the strips of a stockbook. Do not use ordinary paper envelopes, which are acidic, and do not use rubber bands or paper clips on anything.

Storing Them Properly

The rule that matters most: never use glue or sticky tape. Both are permanent, both stain, and both destroy a stamp’s value outright.

• Stamp hinges are fine for used stamps. Lightly moisten the short flap and fix it to the back of the stamp just below the top perforations, then moisten the long flap and press it to the page. Use peelable hinges and as little moisture as you can.
• Stamp mounts are clear sleeves that hold the stamp without touching the gum. They cost more, and are the right choice for mint stamps, because a hinge always disturbs the gum.
• Stockbooks suit stamps you have not finished organising — nothing is attached, so everything can be moved.

Keep albums upright, in a cool, dry room, away from sunlight. Our full guide on how to store stamps to prevent damage covers humidity, light, acid-free materials and the plastics to avoid.

Common Mistakes

• Soaking a cover that should have been kept whole.
• Putting one red envelope in with a hundred white ones.
• Using hot water to hurry things along.
• Peeling a stamp that has not released on its own.
• Drying on newspaper or with heat.
• Assuming a modern self-adhesive will behave like a gummed stamp.
• Putting stamps into an album before they are completely dry — trapped moisture causes mould and sticks stamps to the page.

Where to Go Next

If you want material to practise on, a bag of kiloware is the cheapest education in the hobby: a few hundred stamps to soak, sort and identify for very little money. And if you are still deciding what your collection should be about, go back to How to Start Stamp Collecting with your freshly sorted piles in front of you — the stamps you enjoyed handling most are usually the answer.