International reply coupon (IRC),

Definition of International reply coupon (IRC):

1. An international reply coupon - IRC is a type of voucher accepted in multiple countries in exchange for local postage stamps. Upon turning one in, coupon holders get the minimum postage required for airmail weighing up to 20 grams.

2. A coupon that is traded for the minimum postage of priority airmail that is not registered. Only a member of the Universal Postal Union (UPU) uses an IRC and is required to exchange it. An IRC is used on items that weigh 20 grams or fewer.

3. Only countries taking part in the Universal Postal Union, or UPU, accept IRCs for postage. The UPU is a wing of the United Nations. It coordinates the delivery of global mail, as well as postal policies among member nations. The UPU is based in Bern, Switzerland. The majority of the world’s countries, as well as Vatican City take part in the UPU. The UPU added South Sudan, its most recent member, in 2011.