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An international reply coupon was a voucher you bought at a post office and enclosed with a letter abroad, so the recipient could swap it for stamps to reply. The system dates to a 1906 Universal Postal Union congress. USPS stopped selling IRCs in 2013, and the UPU has voted to end the program on December 31, 2026.
The problem it solved was real: if you wrote to someone in another country and wanted a reply, they would need your country's stamps, which they could not buy at home. The IRC was the fix. You bought the coupon at your post office, slipped it into your letter, and your correspondent exchanged it at their post office for enough stamps to mail a reply. Every UPU member country was required to accept an IRC in exchange for postage, though no country was required to sell them, which is the loophole the whole later history turns on.
| Year | What happened |
|---|---|
| 1906 | The UPU congress in Rome introduces the IRC. |
| 2011 | Royal Mail stops selling IRCs, citing minimal sales. |
| 2013 | USPS discontinues IRC sales for lack of demand. |
| 2025 | Germany's Deutsche Post phases them out; the UPU votes to end the program. |
| 2026 | The IRC program ends December 31; coupons expire after that date. |
Email did most of the damage. By the 2010s, almost nobody was prepaying international replies by mail, and post offices were selling fewer than one coupon per location per year in some countries. The USPS ended sales in January 2013, Royal Mail in December 2011, and others followed through the 2020s. Selling them was a courtesy the numbers no longer supported. One charming footnote: IRCs were famous in amateur radio circles, where operators tucked them into letters with QSL cards as good etiquette, and in 1920 Charles Ponzi built his infamous scheme on the price gaps between countries' coupons.
Probably not where you live, and the clock has nearly run out. A handful of postal services still sold them into 2025, but the UPU's vote to discontinue the program means no new IRCs after December 31, 2026, and existing coupons expire with the program. If you are holding an old coupon as a curiosity, it is now a collector's item, not postage. Do not plan any correspondence around buying one: check your local post office, but expect a no.
For most people, the answer is simply not mail: email and messaging apps erased the use case. When a mailed reply genuinely matters, the modern equivalents are enclosing a prepaid return method you arrange yourself, such as sending funds for postage, or using an international courier's prepaid return label. For one-way letters abroad, the IRC was never needed anyway: it only ever solved the reply side. If you are writing internationally and just need the letter sent, an assistant with LetterAgent can handle US and Canadian recipients, though international destinations beyond those are outside its scope.
Almost nobody, which is why the program is ending. The last real constituency was a thin slice of hobbyists: amateur radio operators exchanging QSL cards across borders, a few philatelists, and occasional official correspondence where protocol demanded a paper reply mechanism. Even among hams, most had switched to enclosing a couple of US dollars, universally understood and instantly spendable, instead of hunting down a coupon their local post office had never heard of. When your product's most loyal users have already found a workaround, discontinuation is just paperwork.
Ready to mail it? Send your letter with LetterAgent: describe it to your AI assistant, approve the exact quoted price, and it is printed and mailed.
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