All About Watermarks

Discover everything you need to know about watermarks on your stamps.

What is a watermark?

Watermarks are letters, symbols, or patterns impressed into the paper used to print stamps.

Which stamps have watermarks?

Many older US stamps have watermarks in the shape of a single- or double-line “USPS.” Modern US stamps do not have watermarks. Foreign stamps can be found with watermarks picturing many different symbols.

How do I find out if my stamp has a watermark?

  1. Gather the materials you need: small clean plastic tray, watermark fluid, tongs, & stamps you want to check for watermarks.
    Tip: Only use substances specially made for use with postage stamps, otherwise you risk damaging or destroying your stamps.
  2. Find a well-lit area to work in and fill your tray with enough watermark fluid to cover a stamp.
    Tip: You don’t need much watermark fluid, it’s better to add a little more than use too much and have the extra go to waste.
  3. Using your tongs, place your stamp face down in the tray and wait a second or two for any marks to appear.
    Tip: Some stamps may have cancellation or printing ink soaked through to the back. You may have to look closely and carefully to identify potential watermarks. The best way to determine if a dark spot is a watermark or not is to remove the stamp from the watermark fluid and see if the mark disappears. If it does, it is a watermark. If it remains, it is not.

Top Tip: It’s helpful to have a reference guide on hand (like the one above from the Scott Specialized Catalogue of United States Stamps & Covers) with examples of how watermarks may appear on your stamps.

Fun Facts About Watermarks on U.S. Stamps

Watermarks were introduced in 1895 as a way to deter counterfeiting. Most US stamps issued from that year to 1917 were printed on watermarked paper, with the very last being in 1938.

Watermarks consist of translucent impressions which allow more light to travel through the paper in affected areas. This design was created by pressing a molded wire form (called a dandy roll) into wet paper pulp before the stamps were printed.

For US stamps, only two watermarks were ever used: “USPS” double-line from 1895 onward and single-line beginning in 1910 & “USIR” watermarks beginning in 1898 for Revenue stamps ONLY. Watermarks can appear reversed, inverted, or both.

Did You Know?

Some Great Britain stamps picture watermarks in the shape of crowns while some stamps of India picture elephant watermarks. Other countries have interesting and unusual symbols in their watermarks, too. That’s why many people enjoy collecting watermarked stamps – it’s like going on a treasure hunt!

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    1. We are not aware of lighter fluid affecting the gum. Lighter fluid has been used for years with no mention of gum disturbance. Mystic recommends using Clarity Watermark Fluid due to it’s non-flammable, non-toxic and odorless properties. Clarity Watermark Fluid is available on our website and it’s what our Processing department uses every day to detect watermarks. https://www.mysticstamp.com/Products/Supplies/LS115/USA/

    1. Watermarks are difficult to see. Sometimes it’s only a speck on the stamp.

      Check out the Scott Specialized Catalog for US watermarks. For the 2018 Catalog, look at pages 29A-30A in the introduction. https://www.mysticstamp.com/Products/Supplies/KS378/USA/ You may be able to find the Specialized Catalog at the library.

      Foreign Watermarks are typically found with the country of issue in Scott Catalog volumes 1-6.

    1. Not for US stamps. Some foreign stamps have very prominent watermarks, so it’s possible you’d be able to see them. But, unfortunately, you can’t watermark U.S. stamps attached to envelopes.

    1. No, not for for U.S. stamps. But you may be able to for some stamps issued by other countries, as they may have very prominent watermarks.

  1. So I bought Clarity and was wondering after it has been applied, will the watermark be present permanently?

    1. No. As the fluid evaporates, the watermark disappears. You could use your phone camera to make a record of it.

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