What happens when you drop the country from a port code?

Of 24,099 sea and air locations in our 21 October 2026 UN/LOCODE snapshot, 18,047 (74.9%) share their three-character suffix with at least one other full code. Removing the country prefix makes those locations ambiguous within this dataset.

This measures code reuse, not shipping mistakes. We did not observe shipments, delays or financial losses.

What we counted

SAN does not identify just San Diego

The snapshot contains 15 full codes ending in SAN, including US SAN for San Diego, AR SAN for Santa Ana and JP SAN for Sanbonmatsu. The country prefix separates them. LAX appears in three full codes and SBH in five.

A suffix that matches an airport code is not evidence that every location using it is that airport. UNECE describes UN/LOCODE as country plus location, and says the IATA column is populated when it differs from the location element. An empty IATA cell alone does not settle whether an airport code exists.

Method and reproduction

1. Start with FreightStow’s checked-in UNECE pre-release snapshot, retrieved on 2026-10-21. It includes sea or air functions, excludes change indicator X and statuses RQ, RR, QQ and XX, and combines alternate names under the same full code.
2. Count each unique five-character UN/LOCODE once. These are location records, not a count of physical terminals or operating airports.
3. Group records by the final three characters. Mark a group as reused when it has more than one full code. Because full codes are unique, reuse here is across country or territory prefixes.
4. Sum records in reused groups and divide by all records: 18,047 ÷ 24,099 × 100 = 74.9%, rounded to one decimal place.

The downloadable CSV contains every distinct suffix, its record count and its full codes. Download the frozen input and reproduction script into the same folder, then run node reproduce-2026-10.mjs --standalone with Node.js. In the FreightStow source checkout, node scripts/build-research-data.mjs --check verifies the published files. The JSON download records the input checksum and the upstream archive checksum.

This is a filtered snapshot of a pre-release, not the full UN/LOCODE directory or a current operational routing list. Inland-only locations are excluded. Later editions and different filters will produce different counts. We did not test whether an individual facility is open or handles cargo.

SHA-256 of the input JSON: 4ad35700ef813af61801cbfac0fb7b155018cc697a5f605609e4af48a0d0a7ab

What to put on the document

Keep the country prefix when a field asks for UN/LOCODE. When it asks for IATA, check the airport and country rather than copying the suffix of a nearby port. FreightStow’s port and airport finder shows the two code systems separately.

Location data is derived from UNECE and shared with attribution under CC BY 4.0. FreightStow filtered the source and calculated these counts. UNECE has not endorsed the analysis.