# How does the government check the validity of postage stamps? **URL:** \ **Category:** Factual Questions\ **Created:** [March 12, 2007, 11:42pm UTC](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680 "2007-03-12T23:42:57Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![KDS444](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kds444/32/20294_2.png) [@KDS444](https://boards.straightdope.com/u/KDS444)\ **Post date:** [February 7, 2019, 12:09am UTC](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680/21 "2019-02-07T00:09:01Z")
Here we are, 12 years later, and there is still no real answer to this question. I can tell you this: I occasionally get packages from a certain eBay seller who mails everything with stamps (as opposed to a preprinted label) and the packages always arrive with no cancellation on that postage. And when desperate for an extra stamp once or twice, I have removed one of those stamps and placed it on an envelope that I have then sent, and everything has always arrived at its destination as anticipated. I didn’t fake these stamps— they were real stamps. But there was no automated cancellation of them once they were used the first time. So while the Post Office may be able to detect a real stamp from a fake one, as of 2018 it is unable to detect a used stamp from a new one if not canceled with a rubber stamp or postal ink pen of some kind. Which is sort of relevant. ---
**Author:** ![nearwildheaven](https://avatars.discourse-cdn.com/v4/letter/n/90db22/32.png) [@nearwildheaven](https://boards.straightdope.com/u/nearwildheaven)\ **Post date:** [February 7, 2019, 12:26am UTC](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680/22 "2019-02-07T00:26:46Z")
> [@butler1850](#): > > How does the likes of [stamps.com](http://stamps.com) do it then? You can print your legal stamp using your home printer. > > What’s to stop me from printing a sheet, then copying multiple times on my color copier/scanner/printer? I know this is a zombie thread, but chances are, that [stamps.com](http://stamps.com) paper is coated with the identifying chemical. ---
**Author:** ![Peter\_Morris](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/peter_morris/32/359_2.png) [@Peter\_Morris](https://boards.straightdope.com/u/Peter_Morris)\ **Post date:** [February 7, 2019, 3:10am UTC](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680/23 "2019-02-07T03:10:12Z")
On your home printer? ---
**Author:** ![panache45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/panache45/32/64_2.png) [@panache45](https://boards.straightdope.com/u/panache45)\ **Post date:** [February 7, 2019, 3:55am UTC](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680/24 "2019-02-07T03:55:26Z")
Way back in the early '70s, when I was an Art Director, I did a special job from a wealthy client. The man knew that, at the time, I collected Japanese postage stamps. In appreciation, he gave me a set of maybe 20 very early Japanese stamps. I happened to own a book that described all known Japanese counterfeits… sure enough, they were all fakes; there were tiny discrepancies in every one. But they were beautiful fakes. I may still have them around somewhere. ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [February 7, 2019, 3:58am UTC](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680/25 "2019-02-07T03:58:25Z")
> [@nearwildheaven](#): > > I know this is a zombie thread, but chances are, that [stamps.com](http://stamps.com) paper is coated with the identifying chemical. Each stamp that is printed from [stamps.com](http://stamps.com) has a unique 2-d barcode. ---
**Author:** ![psychonaut](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/psychonaut/32/4655_2.png) [@psychonaut](https://boards.straightdope.com/u/psychonaut)\ **Post date:** [February 7, 2019, 7:40am UTC](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680/26 "2019-02-07T07:40:01Z")
> [@scm1001](#): > > The canadian post office is not so shy. > > " During the printing process the stamps are tagged with a fluorescent ink on all four edges. Tagging permits stamps affiÌ to envelopes to be detected by machine and is also an antifraud tactic for corporate revenue protection" > > from [http://www.upu.int/philately/en/making\_postage\_stamp.html](http://www.upu.int/philately/en/making_postage_stamp.html) Seeing this post pop up again reminds me of something I forgot to mention last time. In the mid- to late 1990s someone published a book that showed (or purported to show) fake stamps that were successfully used to post letters in Canada. The fake stamps were skilfully designed, resembling contemporary Canadian stamps and also the older engraved variety, but were obvious parodies for anyone who took the time to examine them for a few seconds. I remember, for example, that there was a stamp featuring Preston Manning (then the Leader of the Opposition and a frequent target of jokes and impersonations on sketch comedies). The book presented photographs of envelopes bearing cancelled versions of these stamps. I can’t remember the title or author of the book, but if anyone knows, please enlighten me. I wouldn’t mind getting a copy to see if I can determine whether the cancellations were also fake, or whether the author really did send them through the mail. ---
**Author:** ![psychonaut](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/psychonaut/32/4655_2.png) [@psychonaut](https://boards.straightdope.com/u/psychonaut)\ **Post date:** [February 7, 2019, 7:46am UTC](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680/27 "2019-02-07T07:46:19Z")
> [@Peter\_Morris](#): > > Would anybody really go to the trouble of forging stamps just to save a few pence on postage? Too much trouble for too little profit. [A _Telegraph_ article from 2013](https://www.telegraph.co.uk/news/newstopics/howaboutthat/10411201/Royal-Mail-man-makes-own-silly-stamps-featuring-his-own-face-and-sends-letters-for-free.html): > [@](#): > > **Royal Mail: man makes own ‘silly’ stamps featuring his own face and sends letters for free > A man claims he has been sending letters for free for years using DIY stamps featuring his own face** > > Angus McDonagh, 64, says he has duped Royal Mail with over a hundred of his designs on letters posted all over the world. > > Many feature his own face in the Queen’s traditional side profile complete with a comic eye patch or weird hat. > > At Christmas he has created some of himself with a white Santa beard while others have used family photos. > > Mr McDonagh, an architect who calls himself an ‘anarchist philatelist’, began his personal freepost system three years ago in protest at bland stamp design. ---
**Author:** ![Alessan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/alessan/32/465_2.png) [@Alessan](https://boards.straightdope.com/u/Alessan)\ **Post date:** [February 7, 2019, 10:38am UTC](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680/28 "2019-02-07T10:38:28Z")
It’s a matter of cost effectiveness, really. Is it worth spending, say, $10 million on security measures in order to catch $5 million worth of fraud? ---
**Author:** ![Thudlow\_Boink](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/thudlow_boink/32/320_2.png) [@Thudlow\_Boink](https://boards.straightdope.com/u/Thudlow_Boink)\ **Post date:** [February 7, 2019, 1:06pm UTC](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680/29 "2019-02-07T13:06:40Z")
I know this is an old thread, but I’m wondering if it’s fair for the OP to identify the USPS with “the government.” ---
**Author:** ![psychonaut](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/psychonaut/32/4655_2.png) [@psychonaut](https://boards.straightdope.com/u/psychonaut)\ **Post date:** [February 7, 2019, 1:35pm UTC](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680/30 "2019-02-07T13:35:23Z")
> [@Thudlow\_Boink](#): > > I know this is an old thread, but I’m wondering if it’s fair for the OP to identify the USPS with “the government.” But the OP doesn’t make this identity. They ask how the government identifies USPS stamps. Postal fraud is the purview of the US Postal Inspectors, a federal law enforcement branch. (Even so, is it really so wrong to casually refer to the USPS as “the government”? It is an organization mandated by the constitution and established by the government, even if they have a fairly hands-off approach to running it.) ---
**Author:** ![jjakucyk](https://avatars.discourse-cdn.com/v4/letter/j/3d9bf3/32.png) [@jjakucyk](https://boards.straightdope.com/u/jjakucyk)\ **Post date:** [February 7, 2019, 2:00pm UTC](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680/31 "2019-02-07T14:00:07Z")
> [@KDS444](#): > > …packages always arrive with no cancellation on that postage…I didn’t fake these stamps— they were real stamps. But there was no automated cancellation of them once they were used the first time. I’m curious about this too. I’ve received a few letters with no visible cancellation stamp, so what’s to stop me from peeling it off and reusing it? Could the USPS be using ultraviolet ink or something else that’s not visible, or is this just a goof, like their stamper ran out of ink? ---
**Author:** ![Channing\_Idaho\_Banks](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/channing_idaho_banks/32/250_2.png) [@Channing\_Idaho\_Banks](https://boards.straightdope.com/u/Channing_Idaho_Banks)\ **Post date:** [February 7, 2019, 2:01pm UTC](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680/32 "2019-02-07T14:01:20Z")
Decades ago I read that the technology was so simple that you could mail a package with a $0.10 stamp and it would go through because the machines recognize the phosphorus on the ten cent stamp, but weren’t smart enough to be able to count how many there were. It was also noted that stamps for $0.01 or $0.05 did not have the phosphorus on them. ---
**Author:** ![BwanaBob](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bwanabob/32/2985_2.png) [@BwanaBob](https://boards.straightdope.com/u/BwanaBob)\ **Post date:** [February 7, 2019, 3:24pm UTC](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680/33 "2019-02-07T15:24:30Z")
> [@jjakucyk](#): > > I’m curious about this too. I’ve received a few letters with no visible cancellation stamp, so what’s to stop me from peeling it off and reusing it? Could the USPS be using ultraviolet ink or something else that’s not visible, or is this just a goof, like their stamper ran out of ink? Let me know how successful you are in trying to remove a self-adhesive stamp from an envelope. ---
**Author:** ![psychonaut](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/psychonaut/32/4655_2.png) [@psychonaut](https://boards.straightdope.com/u/psychonaut)\ **Post date:** [February 8, 2019, 8:08am UTC](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680/34 "2019-02-08T08:08:05Z")
> [@BwanaBob](#): > > Let me know how successful you are in trying to remove a self-adhesive stamp from an envelope. It’s not so hard if the stamp doesn’t have those annoying perforations in the middle. In fact, I think it’s easier to peel these off than the regular non-self-adhesive kind. Are all self-adhesive USPS stamps perforated in the middle now? I know that the definitive Machin stamps of the UK are, which is too bad because I get an awful lot of mail from the UK with uncancelled stamps. I’ve yet to see any self-adhesive German stamps with the perforations, but Deutsche Post almost always cancels stamps. ---
**Author:** ![Lord\_Feldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lord_feldon/32/341_2.png) [@Lord\_Feldon](https://boards.straightdope.com/u/Lord_Feldon)\ **Post date:** [February 8, 2019, 8:30am UTC](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680/35 "2019-02-08T08:30:47Z")
> [@psychonaut](#): > > Are all self-adhesive USPS stamps perforated in the middle now? I know what you’re talking about (I’ve also seen it on Machin stamps), but I don’t think I’ve ever seen that feature on a US stamp. ---
**Author:** ![MEBuckner](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mebuckner/32/2896_2.png) [@MEBuckner](https://boards.straightdope.com/u/MEBuckner)\ **Post date:** [February 8, 2019, 12:50pm UTC](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680/36 "2019-02-08T12:50:03Z")
> [@Thudlow\_Boink](#): > > I know this is an old thread, but I’m wondering if it’s fair for the OP to identify the USPS with “the government.” A couple of citations in support of the point already made by **psychonaut** above: [39 U.S. Code § 201](https://www.law.cornell.edu/uscode/text/39/201): > [@](#): > > There is established, as an independent establishment of the executive branch of the Government of the United States, the United States Postal Service. [39 U.S. Code § 101](https://www.law.cornell.edu/uscode/text/39/101): > [@](#): > > The United States Postal Service shall be operated as a basic and fundamental service provided to the people by the Government of the United States, authorized by the Constitution, created by Act of Congress, and supported by the people. ---
**Author:** ![BwanaBob](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bwanabob/32/2985_2.png) [@BwanaBob](https://boards.straightdope.com/u/BwanaBob)\ **Post date:** [February 8, 2019, 1:00pm UTC](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680/37 "2019-02-08T13:00:45Z")
> [@psychonaut](#): > > It’s not so hard if the stamp doesn’t have those annoying perforations in the middle. In fact, I think it’s easier to peel these off than the regular non-self-adhesive kind. Are all self-adhesive USPS stamps perforated in the middle now? I know that the definitive Machin stamps of the UK are, which is too bad because I get an awful lot of mail from the UK with uncancelled stamps. I’ve yet to see any self-adhesive German stamps with the perforations, but Deutsche Post almost always cancels stamps. No but what we stopped doing is adding a water soluble layer between the self adhesive material and the actual stamp. The first generation of self-adhesive stamps could be soaked off the envelope with warm water without any damage to the stamp. Theoretically, if one received a letter where the stamp had not been cancelled, it could have been soaked and reused with the “cheater” using their own glue. Current stamps will not soak off. ---
**Author:** ![drachillix](https://avatars.discourse-cdn.com/v4/letter/d/48db29/32.png) [@drachillix](https://boards.straightdope.com/u/drachillix)\ **Post date:** [February 8, 2019, 3:57pm UTC](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680/38 "2019-02-08T15:57:29Z")
There are several ways to “cheat” a stamp especially if you are sending snail mail to a friend. Stamps can be considered legal tender for certain debts and can be used to pay IRS tax debt. ---
**Author:** ![psychonaut](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/psychonaut/32/4655_2.png) [@psychonaut](https://boards.straightdope.com/u/psychonaut)\ **Post date:** [February 8, 2019, 4:01pm UTC](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680/39 "2019-02-08T16:01:50Z")
> [@drachillix](#): > > Stamps can be considered legal tender for certain debts Which debts would those be? ---
**Author:** ![Peter\_Morris](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/peter_morris/32/359_2.png) [@Peter\_Morris](https://boards.straightdope.com/u/Peter_Morris)\ **Post date:** [February 8, 2019, 4:50pm UTC](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680/40 "2019-02-08T16:50:02Z")
IRS tax debt. He just told you. [Previous page](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680.md?page=1) [Next page](https://boards.straightdope.com/t/how-does-the-government-check-the-validity-of-postage-stamps/395680.md?page=3)