Mailing a letter to Canada is one of the few postage questions where the answer is genuinely simple, and most people still get it wrong because they assume it works like domestic mail. It does not. One stamp covers it, but not the stamp you are probably holding.
This page sets out what USPS charges to send a letter to Canada and to the rest of the world, which stamp covers it, and what happens when a Forever stamp is used instead. All rates are the USPS prices that took effect on July 12, 2026.
One Global Forever stamp covers a one-ounce letter to any country
The Global Forever stamp costs one dollar and seventy-five cents and pays the postage on a First-Class Mail International letter weighing one ounce or less, addressed to any country that USPS delivers to. The Global Forever stamp is priced as a single flat rate rather than by destination, so the postage on a letter to Canada is identical to the postage on a letter to Japan, to Germany, or to Australia.
The absence of destination pricing is the entire point of the Global Forever stamp. A sender does not need to identify a zone, consult a country table, or calculate anything, because the same stamp covers every destination at the same price. A round Global Forever stamp affixed to a standard envelope weighing one ounce or less is complete postage for international mail.
The Global Forever stamp also holds its value across rate changes in the same way a domestic Forever stamp does. A Global Forever stamp purchased before a price increase remains full postage for a one-ounce international letter after the increase, regardless of the price printed at the time of purchase, because the Global Forever stamp carries no printed denomination.
What a domestic Forever stamp actually covers on international mail
A domestic Forever stamp is worth eighty-two cents, which is the current First-Class Mail letter rate. A domestic Forever stamp is not invalid on international mail, and a domestic Forever stamp does contribute its full eighty-two cents of value toward the international rate, but a single domestic Forever stamp does not cover the one dollar and seventy-five cent international rate on its own.
The shortfall is ninety-three cents, and mail bearing insufficient postage is either returned to the sender for additional postage or delivered with postage due collected from the recipient. Neither outcome is desirable on a letter that has already crossed a border.
| What is on the envelope | Value | Result on a 1 oz letter to Canada |
|---|---|---|
| One Global Forever stamp | $1.75 | Correct postage |
| One domestic Forever stamp | $0.82 | Short by $0.93 |
| Two domestic Forever stamps | $1.64 | Short by $0.11 |
| Three domestic Forever stamps | $2.46 | Overpays by $0.71 |
| Two domestic Forever stamps plus $0.11 in denominated stamps | $1.75 | Correct postage, exactly |
Two domestic Forever stamps are the combination that catches most senders, because one dollar and sixty-four cents looks close enough to one dollar and seventy-five cents to pass unnoticed. Two domestic Forever stamps are eleven cents short, and eleven cents is enough to trigger a postage due assessment.
Where the Global Forever stamp stops covering the mail
The flat rate applies to a First-Class Mail International letter weighing one ounce or less. Three conditions move a piece of mail outside that definition, and in each case the Global Forever stamp is no longer complete postage.
Mail that weighs more than one ounce is charged additional international postage that varies by destination country, which means the flat-rate simplicity ends at the one-ounce mark. Mail that exceeds the dimensions permitted for a letter is priced as an international large envelope, which is a separate rate category. Mail that contains goods rather than correspondence is subject to customs requirements and is not a First-Class Mail International letter at all, regardless of weight.
An international postcard is charged the same one dollar and seventy-five cent rate as a letter, so a Global Forever stamp is complete postage on a postcard to any country, and USPS does not publish a separate lower international postcard rate.
How to reach exactly $1.75 from a drawer of old stamps
USPS accepts any valid United States stamp at the face value printed on the stamp, and stamps may be combined in any quantity to reach the required postage. A domestic Forever stamp counts as eighty-two cents in any such combination. Overpayment is not refunded, so a combination that exceeds one dollar and seventy-five cents is money that is not recovered.
Older denominated stamps are the efficient way to close the gap, because the increments needed are small and awkward to reach with Forever stamps alone. Two domestic Forever stamps plus eleven cents in denominated stamps produces exactly one dollar and seventy-five cents, and one domestic Forever stamp plus ninety-three cents in denominated stamps does the same.
Still holding stamps you will never mail?
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