Most stamps are worth a few cents, and a valuable stamp is usually one of four things: an issue from before about 1900, a mint stamp with its original gum untouched, a known error or variety, or a sound, well-centered copy of a stamp that is scarce in that condition. Age by itself does not do it. Billions of stamps were printed from the 1920s onward, people saved them by the album, and a used commemorative from 1950 is worth the same today as it was then, which is a few cents. The quick way to sort a pile is to pull out anything from the nineteenth century, anything mint with gum, anything with a strange look, and anything in a country's first few issues, then check those against a catalog and a dealer's price list. What is left is usually worth about $10-50 a shoebox as a lot.
Quick answer
- Pre-1900 stamps, mint stamps with undisturbed gum, and errors are where the value is. Used stamps from the 1920s onward are mostly worth about 5-25 cents each.
- Condition decides the price: a thin, a tear, a crease or a heavy cancel cuts the value by 50 to 90 percent.
- Catalog value is a retail reference. Dealers pay about 10 to 40 percent of it for ordinary material, more for scarce stamps in sound condition.
How to check a stamp, step by step
- Identify it. Note the country, the denomination, the design and the color. Most countries' stamps can be matched in the Scott catalog (United States), Stanley Gibbons (British and Commonwealth) or Michel (Europe); public libraries often have them. Online, the Colnect database and auction archives work for a first match. Write down the catalog number.
- Check the date. Stamps from before about 1900 are where most of the value lives, and anything from the 1840s to 1870s deserves a careful look. A stamp from the 1930s to the present is almost always common unless it is an error or a high denomination.
- Turn it over. For a mint stamp, the back decides the price. Original gum that has never been hinged (called MNH or never hinged) is the top grade. A hinge remnant or a hinge mark cuts the value by half or more on twentieth century stamps. Regummed stamps, where someone has applied new gum to a washed stamp, are a common fraud; under a loupe the gum runs over the perforation tips, which original gum never does.
- Hold it up to the light. Look for thins, where the paper is thinner from a hinge being torn off, and for creases, tears and pinholes. A thin is the most common fault and takes 50 to 90 percent off the price. Watermark fluid, which is a lighter fluid sold for stamps, and a black tray show watermarks, which separate valuable printings from common ones on many classic issues.
- Look at the centering and the perforations. Compare the margins on all four sides. A stamp with the design sitting evenly inside its margins is worth several times one that is cut into the design. Count the perforations along two centimeters with a perforation gauge; different gauges of the same design can differ by a hundred times in price.
- Check the cancel. On a used stamp, a light, clear postmark is best. A heavy black smudge that hides the design lowers value sharply. A clear dated town cancel on a classic stamp can add value. Pen cancels on nineteenth century stamps are a deduction but on some issues are the only cancels that exist.
- Look for anything odd. Missing colors, inverted centers, missing perforations on one side, doubled printing, wrong paper, a stamp printed on the gum side. Errors are where single stamps reach four and five figures. Check that the oddity is a real error and not damage, trimming or a faded stamp.
- Check the margins and the edges. Imperforate stamps from the 1840s to 1860s need four clear margins to reach full catalog. A copy cut into the design on one side is worth a fraction. Look for reperforated edges on perforated stamps: new perforations are too even and the tips are too clean.
What stamps are worth: honest anchors
| Stamp or group | What it is | Typical value, as of late 2026 |
|---|---|---|
| Used US and world commemoratives, 1920s to today | The bulk of every inherited album | About 5-25 cents each, sold by the shoebox for about $10-50 |
| Mint US stamps, 1940s to today, never hinged | Still valid postage | About 60-85 percent of face value from a dealer; sold as discount postage |
| Mint US stamps, 1920s and 1930s, hinged | Common but older | About $0.25-5 each, some high values more |
| Used US classics, 1861 to 1890s, sound copies | Common Bank Note issues | About $1-30 each, more for clean well-centered copies |
| US 1847 5 cent Franklin, used, sound | The first US stamp | About $300-700 |
| US 1893 Columbian $1 to $5, used | High values of the first commemoratives | About $400-2,500 each |
| US 1918 Inverted Jenny | The famous airmail error, 100 exist | About $1-2 million, depending on condition |
| Penny Black, 1840, used | The first adhesive stamp in the world | About $100-400 for a sound copy with four margins, more for better |
| German 1920s inflation stamps, mint or used | Printed by the billion | About 5-50 cents each |
| Plate blocks, US, 1940s to today | Blocks of four with the plate number | Face value to about 2 times face; mostly sold as postage |
| First day covers, 1940s to today | Envelopes with a stamp canceled on its first day | About $0.50-3 each, with exceptions for early or rare cachet makers |
| Chinese 1980 Year of the Monkey, mint | Modern, heavily collected in China | About $1,500-3,000 |
These are market prices, meaning what a sound copy sells for. Catalog value runs higher, and a dealer buying from you pays less again. A collection that "catalogs" at $5,000 commonly sells for about $500-1,500, because most of the catalog value is made up of minimum values on common stamps that no one pays. Our guide to an inherited stamp collection's worth covers how to approach the whole album.
Condition and what it does to price
| Condition point | Effect on value |
|---|---|
| Mint, never hinged, original gum | Full price, often 2 to 5 times the hinged price for twentieth century stamps |
| Mint, lightly hinged | About 40-60 percent of never hinged on modern stamps, closer on classics |
| Mint, no gum or regummed | About 10-30 percent of original gum price; regummed stamps sold as original are a fraud |
| Used, light clear cancel | Full used price |
| Used, heavy cancel or pen cancel | About 20-50 percent |
| Well centered, margins even on all sides | A premium of 2 to 10 times on scarce stamps, graded by third-party services |
| Poor centering, design cut by perforations | About 10-30 percent |
| Thin, crease, tear, pinhole, pulled perforation | About 10-50 percent, and many buyers skip faulty stamps entirely |
| Fresh color, unfaded | Full price; sun-faded or toned copies drop sharply |
Grading matters more now than it used to. The PSE and PF grading services issue grading reports with a numerical grade for centering and condition, and a classic stamp graded 95 or above can sell for many times catalog. The grading fee is about $20-60 per stamp, so it only makes sense for stamps with a catalog value in the hundreds.
Mint, used, and why the back matters most
Collectors of twentieth century stamps pay for undisturbed gum. A 1930s commemorative that is never hinged may be worth $2 while the hinged copy next to it is worth 25 cents. The difference is only visible from the back under good light. Look for a small translucent rectangle where a hinge sat, a thinned area where one was torn off, or glossy, shiny new gum that covers the perforation tips, which means regumming. On stamps older than about 1890, hinged copies are the norm and the never hinged premium is smaller, but regumming is still common and still a reason to be careful with any high value mint classic.
For used stamps the back shows thins. Hold the stamp over a black surface and look for lighter patches, or use watermark fluid, which shows thins as dark spots. Repaired tears and filled thins are harder to see and are the reason expensive stamps are sold with an expert opinion.
What a photo can show
A good scan or photo at close range shows the design, the color, the cancel, the centering, obvious faults, perforation damage and the overall look of the gum. It can place a stamp in a catalog, flag an error, and separate the common look of a 1950s commemorative from the look of an 1860s classic. It cannot gauge perforations exactly, cannot show a watermark, cannot distinguish a careful regumming from original gum, and cannot see a filled thin. Those are the tests that stand between a $20 stamp and a $2,000 one, and they belong with a dealer or an expertizing committee. Related paper from the same box, such as covers and cards, is covered in our guide to old postcards worth anything.
How WorthPic reads stamp photos
WorthPic runs on the newest and most capable AI model available, tuned for exactly this kind of identification. For a stamp it works from the design and the paper: it reads the country, denomination, design and color to match the issue, judges centering from the margins, reads the cancel and its weight, looks for visible faults, missing perforations or color shifts, and, if you include the back, reads the state of the gum and any hinge remnants. It gives an honest value range for what is visible, and most of the time that range is honest in the other direction too, because most stamps are common and it says so plainly. When a detail cannot be seen, it says which photo would settle it: the back under raking light for gum and thins, or a photo with a perforation gauge laid over the edge. It identifies and estimates. It does not grade or expertize; for a stamp that looks like a classic rarity or an error, a philatelic dealer or an expertizing service is what settles it.
Common mistakes
- Taking catalog value as sale value. Dealers pay about 10-40 percent of catalog for ordinary material.
- Assuming old means valuable. A used 1930s stamp is about as valuable as a used 2020s stamp.
- Removing stamps from envelopes. A classic stamp on its original cover with a clear postmark is often worth more than the stamp alone.
- Peeling hinges off mint stamps. That is how thins happen.
- Storing in damp places or in plastic that is not archival. Toned, stuck-down or foxed stamps lose most of their value.
- Buying grading for common stamps. A grading fee of $20-60 on a $3 stamp is money gone.
- Mistaking a color variety described online as rare for the common shade in hand. Shades need comparison copies and good light.
What to photograph
- The front of the stamp, straight on, filling the frame, in daylight or under a neutral lamp.
- The back of the stamp under light from a low angle, so gum, hinge marks and thins show.
- The stamp held to a window or over a black tray if you can see a thin or a watermark.
- The whole envelope if the stamp is still on one, both sides.
- A perforation gauge laid over the edge, if you have one.
- The album page, to show the context and any notes a previous owner made.
When to get it looked at in person
- A philatelic dealer who belongs to the American Philatelic Society or the American Stamp Dealers Association can price a collection in an hour and make an offer. Most will look at a few stamps at no charge; a written appraisal of a whole collection is about $50-150 an hour.
- An expertizing service such as the Philatelic Foundation or APEX issues an opinion on genuineness and condition for about $20-100 per stamp. Required for any stamp with a catalog value in the hundreds before selling, and the only defense against regumming and repairs.
- A stamp society or club will often look at a box of inherited stamps for nothing and point out anything worth pursuing.
- A stamp auction house is the route for classic rarities, errors and specialized collections, where competitive bidding beats a dealer's offer.
Paper money from the same box follows similar rules on condition; our guide to old dollar bills worth money covers it.