Seiko serial number lookup
Enter the serial number engraved on your watch and we date it instantly, using the same reference tables we use to date the vintage Seiko watches we auction every week.
The 4 digits before the dash on the caseback, e.g. 6139. It pins the exact decade.
Where to find the serial number
On the caseback you'll find two engravings: the caliber-case code (e.g. 6139-6002) and the 6–7 character serial. The first serial digit is the year's last digit, the second character the month (1–9 = Jan–Sep, O = Oct, N = Nov, D = Dec). Enter the caliber too — the 4 digits before the dash — and the tool pins the exact year.
From our Seiko archive
Other Seiko watches we have handled — shown for context; they are not the exact model on this page.
Seiko Sportsmatic Deluxe 1965
Seiko Lord Matic 1971
Seiko Sportsmatic 5 Deluxe 1964
Seiko Lord Matic 1973
Seiko Sportsmatic 5 Deluxe 1964
Seiko Marvel 1957
Seiko Crown 1963
Seiko Advan 1973
Caliber production windows
| 6602 | 1961–1968 |
| 6206 | 1963–1968 |
| 6619 | 1963–1968 |
| 8306 | 1963–1968 |
| 6217 | 1964–1969 |
| 6216 | 1965–1968 |
| 6119 | 1966–1977 |
| 4006 | 1966–1978 |
| 6145 | 1967–1975 |
| 6146 | 1967–1975 |
| 5106 | 1968–1971 |
| 5126 | 1968–1971 |
| 4520 | 1968–1972 |
| 4522 | 1968–1972 |
| 4500 | 1968–1973 |
| 4502 | 1968–1973 |
| 5605 | 1968–1975 |
| 5621 | 1968–1975 |
| 5625 | 1968–1975 |
| 5626 | 1968–1975 |
| 5606 | 1968–1976 |
| 6106 | 1968–1976 |
| 6117 | 1968–1976 |
| 6105 | 1968–1977 |
| 7005 | 1969–1977 |
| 7006 | 1969–1977 |
| 6139 | 1969–1979 |
| 6138 | 1970–1979 |
| 7016 | 1971–1977 |
| 6306 | 1976–1981 |
| 6309 | 1976–1988 |
| 7009 | 1976–1988 |
| 7548 | 1978–1985 |
Reference data: community-documented tables (verified June 2026) refined with our own archive of dated watches. Serial dating gives production dates, not sale dates.
FAQ
Where is the serial number on a Seiko watch?
On the caseback, engraved into the steel. On vintage pieces it can be faint — angle the watch against the light. If the caseback has been polished heavily, the serial may be partially lost.
How accurate is this lookup?
As accurate as the underlying system allows. Seiko and Citizen serials encode the production year and month directly, so with the caliber known the result is exact. Omega serials map to production ranges, so the year is approximate within one to three years.
Why do I get several possible years?
The serial only encodes the last digit of the year. The caliber's production window normally pins the decade — enter the caliber from your caseback and the result usually collapses to a single year.
Does this work for modern watches?
It is built for vintage. Omega serials after 2019 are randomized and cannot be dated by number at all. Recent Seiko and Citizen serials still encode year and month, but the decade ambiguity grows without a documented caliber window.
Ready to hunt for your own?
More than 100 vintage watches go under the hammer every week.