LetterAgent
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Home > Guides > Do Canadian stamps expire?
No. Canada Post's Permanent stamps carry the letter P instead of a dollar value and stay valid for domestic lettermail no matter how rates change. Older stamps with a printed denomination are still good for their face value: combine them to reach the current postage. Like US Forever stamps, they never need topping up.
| Stamp type | What it means |
|---|---|
| Permanent (marked "P") | Always covers the standard domestic letter rate, whatever today's price is |
| Denominated (shows a dollar value) | Worth its face value forever; stack several to reach current postage |
| Commemorative | Same rules as above, depending on whether it's a P stamp or denominated; collectors just prefer not to use them |
| Already postmarked | Dead: reusing a cancelled stamp is a federal offence, not a hack |
Before Permanent stamps existed, every rate increase stranded the stamps in people's drawers: a 51-cent stamp became useless the day the rate went to 52 cents. The P stamp fixed that by standing for "one standard domestic letter" instead of a dollar figure. If you find old stamps with denominations in a drawer, they're still valid for their face value, so a book of ancient 45-cent stamps plus one P stamp can absolutely mail a letter. Just add up the denominations honestly; underpaid mail gets returned or delivered postage-due.
Combining is fine: stick on as many stamps as it takes to reach the postage. Exchanging old stamps for new ones is generally not offered, and Canada Post doesn't buy back or refund unused stamps, so that drawer of commemoratives is a sunk cost you might as well use. One more thing people get wrong: stamps are only valid for the postal service that issued them. Canadian stamps can't mail a letter from the US, and US Forever stamps can't mail one from Canada, even though both are "permanent" in their own countries.
The postage value never expires, but the physical stamp can age. Old lick-and-stick stamps lose their gum and curl at the edges; self-adhesive stamps can dry out if they spent years somewhere hot. A dab of glue stick rescues a stamp whose adhesive gave up, and the postage value is unaffected either way. Store them flat, cool, and dry, and a book of Permanent stamps bought a decade ago works exactly like one bought yesterday. One more quirk people miss: a Permanent stamp covers the basic domestic letter rate, meaning the lightest weight band. A thick or heavy envelope needs extra postage on top, P stamp or not.
Ready to mail it? Send your letter with LetterAgent: describe it to your AI assistant, approve the exact quoted price, and it's printed and mailed.
LetterAgent is a working name. Prices include print, postage, and our service fee. US prices in USD, Canadian prices in CAD (Canadian prices exclude applicable sales tax, added at checkout). Currently in private testing.
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