The Korea Stamp Society (KSS) regularly answers questions from both members and non-members about Korean philately, and one recent inquiry turned out to be a particularly enjoyable puzzle. A collector wrote to us about an airmail cover sent from the Republic of Korea to the Union of Soviet Socialist Republics, which somehow ended up first in the United States before finally reaching its intended destination.
The cover was franked with postage totalling 240 won, and the sender suspected this might be too low for mid-1989 international airmail. To make matters worse, an AI tool they consulted confidently—but incorrectly—claimed the rate should have been USD 4.50. Could we clarify the correct Korean postal rate for a standard airmail envelope at that time?
The cover itself is immediately appealing. It bears three stamps issued in 1989 to commemorate the French Revolution of 1789 (Scott 1538, KPC 1570) and was posted on 14 July 1989, an apt date given the subject of the stamps. The destination was Leningrad, then the second-most important city of the USSR. For reasons still unknown, the letter was misdirected across the Pacific and ended up in Wilmington. Only after this detour was it forwarded onward, as evidenced by a Soviet arrival cancellation marked “CCCP” and Cyrillic manuscript notations on the front of the cover.
Fortunately for researchers, the Korean Philatelic Federation published the Specialized Catalogue of Korean Stamps in 2024, under the editorship of Jin Hur. While the catalogue naturally illustrates every Korean stamp issued since 1884, it also includes a wealth of supporting information, among it comprehensive postal rate tables covering the period from 1945 onwards. This makes it an invaluable reference when questions like this arise.
In the second edition of the catalogue, a table on page 225 lists international postal rates in force between 1981 and 1995. Although presented in Korean, the structure is clear. It shows rates for different categories of mail—letters, aerogrammes, printed matter and small packets—broken down by weight steps and by four international postal zones. These zones reflect distance groupings rather than political boundaries, with nearby destinations such as Japan and China in Zone 1, other East and Southeast Asian countries in Zone 2, and much of the rest of the world, including Europe and North America, falling into Zones 3 and 4. The table also indicates changes over time, notably the unification of airmail surcharges in April 1987, and all rates are expressed in Korean won.
Applying this information to the cover in question gives a clear answer. With a total franking of 240 won, the letter was underpaid. In mid-1989, printed matter sent to a Zone 3 destination required 250 won, while the Zone 4 rate was even higher at 300 won. Depending on how the USSR was classified at the time—either as Zone 3 or Zone 4—the shortfall was at least 10 won.
The cover’s journey brings us to the delightful coincidence of postal codes. Wilmington’s ZIP codes range from 19801 to 19899, a sequence strikingly similar to the postal code used for part of Leningrad at the time. One can easily imagine how, in a moment of human fallibility, “USSR” became “USA” in Korea, and once in the United States, the zip code for “Leningrad” was transformed into “Wilmington.” The result is a genuinely intriguing piece of postal history, created by a simple numerical resemblance.
There is, finally, a pleasing layer of historical irony. The stamps on the cover celebrate the French Revolution and the fall of the Ancien Régime. Just two years later, the regime of the USSR itself would collapse. This single, modest envelope thus connects revolutionary France, late-Cold-War Korea and the final years of the Soviet Union—proof that even an apparently ordinary cover can carry several layers of history along with it.
Information from the table in figure 3 in English
The information in this table is as follows: The image shows a Korean international postal rate table covering multiple periods between 1981 and 1995.
What the table contains:
- Mail categories (left column)
- Letters (서장)
- Aerogrammes (우편엽서)
- Printed matter (인쇄물)
- Small packets (소형포장물)
- Airmail surcharges (항공부가요금)
Weight steps
Examples include up to 10g, 20g, 30g, 40g, 60g, 100g, 250g, 500g, depending on the mail type.
Postal zones (지역)
Rates are given for Zones 1 to 4, reflecting distance-based international groupings.
Three tariff periods
- 1 October 1981 (with zone-based rates shown in four columns)
- 1 April 1987 (intermediate column, with diagonal shading indicating partial applicability or unification)
- 16 October 1995 (updated zone-based rates)
Currency
All amounts are expressed in Korean won (원).
Footnotes at the bottom explain: On 1 October 1981, the Middle East area was reclassified from Zone 4 to Zone 3.
Definitions of each zone, listing example countries and the number of countries included:
- Zone 1: nearby countries (e.g. Japan, China, Hong Kong, Macau)
- Zone 2: Southeast and East Asian countries
- Zone 3: parts of Asia, Oceania, Middle East, Europe, North America
- Zone 4: South America, Africa, Eastern Europe, South Pacific, etc.
On 1 April 1987, airmail surcharges were unified.
Original question
The original question was:
“I have a cover addressed from ROK to USSR, but misdelivered to Wilmington DE, USA, and then forwarded correctly to Leningrad (similar postal codes!) The postage is 240 won, which seems low to me based on survey of other covers. Could you please inform me of the applicable postal rates for airmail standard envelopes at mid 1989. (The AI had a hallucination and reported $4.50 USD.) Many thanks for your help!”
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South Korea concluded a diplomatic tie with then Soviet Russia on 30th September, 1990. This letter was delivered before that. The crew of the post office never thought Korean people would send letters to the former Communist countries like USSR. That’s why the crew erroneously judged that the letter was supposed to be sent to USA rather than USSR. And I assume that he or she might not know about what USSR meant. And 240 won was too low and the crew also neglected the under-rated postage fee. At that time USSR belonged to the 4th zone. The simple FDC with no heavy contents was maybe either 470 won or 600 won.