HEFRON ASSOCIATES HIN Decoder
Hull Identification Numbers beginning with HEF were assigned by the US Coast Guard to HEFRON ASSOCIATES of N ATTLEBORO, MA. The company is recorded as out of business since 1989 — common for older hulls, and useful to know when hunting parts or records. Enter the full 12-character HIN below for build date, model year, and serial — free, no account.
MIC
HEF
Location
N ATTLEBORO, MA
In business
since 1989
Status
Out of business (1989)
HEFRON ASSOCIATES hulls (1989–1989) all use the current HIN format: a month letter (A=January…L=December), a certification-year digit, then two model-year digits.
Free · no account · the HIN is on the transom, upper starboard (right) corner
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HEFRON ASSOCIATES HIN FAQ
What does a HEFRON ASSOCIATES HIN look like?
It starts with the three characters "HEF" — the Manufacturer Identification Code the US Coast Guard assigned to HEFRON ASSOCIATES — followed by a 5-character hull serial and a 4-character date code, 12 characters total. HEFRON ASSOCIATES hulls (1989–1989) all use the current HIN format: a month letter (A=January…L=December), a certification-year digit, then two model-year digits.
Is HEFRON ASSOCIATES still in business?
USCG records list HEFRON ASSOCIATES as out of business since 1989. That's common for older hulls — the HIN still decodes normally, and the out-of-business date helps date the boat and guides parts-hunting toward salvage and owner groups rather than a dealer network.
How do I decode the year on a HEFRON ASSOCIATES HIN?
On current-format HINs the last two characters are the model year and the 9th–10th encode the certification month and year. HEFRON ASSOCIATES hulls (1989–1989) all use the current HIN format: a month letter (A=January…L=December), a certification-year digit, then two model-year digits. Enter the full 12-character HIN above and the decoder works it out, including the legacy formats.
Other builders in MA
Sources: USCG Manufacturer Identification Code database (uscgboating.org, refreshed monthly) · HIN format per 33 CFR 181 subpart C. Cite this page: CarWhere, "HEFRON ASSOCIATES HIN Decoder," carwhere.com/hin-decoder/hef, last verified 2026-06-12.