Effective October 1, 2026, the Postal Service™ is revising the Individual Country Listing for Republic of Korea in Mailing Standards of the United States Postal Service, International Mail Manual (IMM®) to reflect a restriction on mailpieces containing pollen for pollination destined for the Republic of Korea.
This revision is based on a formal request that Korea Post (the designated postal operator of the Republic of Korea) made through the Universal Postal Union via International Bureau Circular 98, dated July 13, 2026.
Mailing Standards of the United States Postal Service, International Mail Manual (IMM)
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Individual Country Listings
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Republic of Korea
Country Conditions for Mailing
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Restrictions
[Revise the entry that starts with “Plants used for planting” to read as follows:]
Plants used for planting or for propagation, including seeds for sowing, seedlings, bulbs, and pollen for pollination, must be accompanied by a phytosanitary certificate. A U.S. mailer must obtain the phytosanitary certificate from the USDA APHIS.
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Although effective October 1, 2026, the Postal Service will incorporate this revision into the next edition of the online IMM, which is available via Postal Explorer® at pe.usps.com.
— Product Classification,
Product Solutions, 10-1-26
