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One Forever stamp covers the first ounce of a standard letter; each extra ounce needs additional postage. A plain one- or two-page letter on regular paper in a standard #10 envelope usually weighs about an ounce, so one stamp does it. Heavier, square, or rigid envelopes need more postage. LetterAgent skips stamps entirely: postage is included in the quote.
| What you are mailing | Postage you need |
|---|---|
| Standard letter, 1 ounce or less (a one- or two-page letter in a #10 envelope) | One Forever stamp |
| Standard letter over 1 ounce (several pages, thick paper, extra sheets) | One Forever stamp plus extra-ounce postage for each additional ounce |
| Square envelope, rigid contents, clasps, or wax seals | First-ounce postage plus the nonmachinable surcharge |
| Large envelope (9x12 or bigger) | Large-envelope (flat) rate, which runs higher than letter postage |
Less than you think. A single sheet of regular office paper weighs a fraction of an ounce, so a one- or two-page letter in a standard envelope lands at about an ounce. You start crossing into extra-ounce territory around four to six pages on regular paper, or sooner with heavy cardstock, photos, or anything tucked inside. When in doubt, a kitchen scale settles it in seconds, or hand the envelope to the post office counter and let them weigh it.
Because they never expire. A Forever stamp bought years ago still covers the first ounce of a standard letter no matter how many times rates have risen since. That makes them the only stamp worth stockpiling: buy a sheet, keep it in a drawer, and stop thinking about rate changes. Older denominated stamps (the ones printed with a cent value) are still valid too, but you have to make up the difference when rates rise, which is exactly the chore Forever stamps eliminate.
You can, but it is usually wasteful. Two Forever stamps pay for two ounces, so on a one-ounce letter you have overpaid. The better fix for an uncertain letter is extra-ounce stamps, which USPS sells specifically for the second and third ounces and cost less than a full Forever stamp. Overpaying by a little is harmless; underpaying gets the letter returned to you or delivered postage-due, which is the worse outcome.
Top right corner of the envelope, right side up. Two details people get wrong: do not tape over the stamp, because the clear tape can make it unreadable to automated equipment and the envelope can be rejected, and do not reuse a stamp, even one that looks uncancelled. If a stamp fell off an envelope you never mailed, that one is fine to reuse. If it went through the mail stream, it is spent.
Canada Post sells permanent stamps that work like Forever stamps: they stay valid for domestic letter mail regardless of rate changes. The same ounce-based logic applies, with Canada Post's own weight steps. As with USPS, square or oversized envelopes cost more than a standard letter stamp covers.
No. LetterAgent includes postage in the per-letter quote: you approve the exact price, pay once, and the letter is printed and mailed. There are no stamps to buy, weigh, or place, and no guessing about ounces.
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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