📮 Intl Mail Rules Change, IRC Abolished

❓ What's changing?

On September 14, 2026, Japan's Ministry of Internal Affairs and Communications (MIC) announced it had approved Japan Post Co., Ltd.'s application to revise its international mail terms and conditions. The approval was granted under Article 68, Paragraph 1 of the Postal Act (Act No. 165 of 1947), after MIC consulted the Information and Communications Council / Postal Services Council and received its report. The planned implementation date is January 1, 2027. The driver is international, not domestic: at the Universal Postal Union (UPU) Congress held in September 2025, the Universal Postal Convention and its Regulations were amended, so comparable changes are moving forward in other countries at the same time. Four main changes follow. First, International Reply Coupons (IRC) are abolished. Postal use has declined worldwide and demand for IRCs had fallen sharply in recent years, so the UPU Congress decided to discontinue them and Japan Post will end the service. Second, for letter-post items containing letters, the size rules and weight conditions are revised and the "small items" size category is deleted. The same category is also removed from the minimum size condition for parcels. Third, to simplify the international mail product line-up, insured mail is limited to priority letter-post items containing only letters and to parcels, and the terms are clarified accordingly. Fourth, when the Convention was amended, the Islamic Republic of Iran filed an accepted reservation allowing it not to bear liability toward the addressee and to limit payment of indemnity to the sender only; this is reflected in the terms. Previously you could buy an IRC and enclose it for an overseas correspondent, a "small items" size category existed, and the scope of insured mail read more broadly than it will. From January 1, 2027, all of this is tidied up.

👥 Who is affected?

• ●Foreign residents in Japan who exchange mail with family or government offices back home
• ●International students, trainees and workers who send documents or parcels abroad
• ●Anyone who encloses International Reply Coupons to get a reply from overseas
• ●Anyone who sends valuables or important documents abroad as insured mail
• ●Anyone who posts items addressed to the Islamic Republic of Iran

🌏 Impact on foreign residents

For foreign residents in Japan, the most familiar situation is dealing with family or government offices back home. If you have been enclosing an International Reply Coupon when asking someone overseas to mail documents back, that option disappears from January 1, 2027. Plan to have the other party cover return postage, or switch to a trackable service. The revised size rules and weight conditions directly affect which category your document or parcel falls into when you send it home. Before posting, check at a post office counter or Japan Post's guidance to see how items previously handled as "small items" will be classified. Because insured mail is limited to priority letter-post items containing only letters, and to parcels, the way you should send important papers such as graduation certificates or contracts in order to keep compensation coverage may change. For mail addressed to the Islamic Republic of Iran, note that indemnity may be payable to the sender only — do not send on the assumption that the recipient can claim compensation.