- The sender of a letter may prepay a reply by purchasing reply coupons that are sold and exchangeable for postage stamps by postal administrations in member countries of the Universal Postal Union.
- International reply coupons (in French Coupons–Reponse Internationaux) are printed in blue ink on paper that has the letters “UPU” in large characters in the watermark. The front of each coupon is printed in French. The reverse side of the coupon shows the text relating to its use in German, English, Arabic, Chinese, Spanish, and Russian.
- Coupons sold in the United States have the selling price printed on them while coupons in other countries may not.
Reply coupons may be requisitioned by Post Office facilities in the same manner as postage stamps. The coupons should be stocked at Post Office facilities that have a demand for them.
- The selling price of a reply coupon in the United States is $2.10. One coupon is exchangeable in any other member country for a stamp or stamps representing the minimum postage on an unregistered air letter. Unused U.S. coupons (that is those with the U.S. selling price stamped on them) may be exchanged only for United States postage stamps by the original purchaser at a discount of 1 cent below the purchase price.
- With the exceptions noted in 381.4d, international reply coupons purchased in foreign countries are exchangeable at U.S. Post Office facilities toward the purchase of postage stamps and embossed stamped envelopes at $0.94 per coupon irrespective of the country where they were purchased.
- When an international reply coupon is sold the Postal Service clerk must place a postmark in the block which is headed control stamp of the country of origin.
- Under Universal Postal Union’s regulations member countries are not required to place a control stamp or postmark on the international reply coupons that they sell. Therefore some foreign issue reply coupons which are tendered for redemption may bear the name of the issuing country (generally in French) rather than the optional control stamp or postmark. Such coupons are exchangeable for U.S. postage as specified in 381.3b.
- A Post Office facility redeeming an unused U.S. coupon must postmark it in the unpostmarked circle. A Post Office facility exchanging a foreign reply coupon must postmark it in the right circle. Post Office facilities must not accept foreign coupons that already bear a Postal Service postmark.
- As of October 11, 2007, only international reply coupons printed by the Universal Postal Union can be redeemed at U.S. Post Offices. The valid version of the international reply coupons printed by the Universal Postal Union is approximately 3.75 inches by 6 inches, has a barcode on the back, and has an expiration date of December 31, 2009. This policy is for international reply coupons issued by the United States as well as for those issued by foreign postal administrations.
- Reply coupons formerly issued by the Postal Union of the Americas and Spain are no longer valid. These coupons are printed in green ink and bear the caption Cupon Respuesta America–Espanol. Customers possessing any of these coupons should return them to their correspondents in the country of issue for redemption through the selling post office.
- Postmasters must process exchanged foreign and redeemed U.S. coupons as prescribed in 426.9 International Reply Coupons (IRCs) Handbook F–1 Post Office Accounting Procedures.