Longines serial number checker, year by year to 1969

On the movement plate, typically near the balance wheel or on the main bridge, which means opening the case. Some vintage models carry it inside the caseback as well. From about 1969 numbers began appearing on the outside of the caseback, and on a modern Longines that is where you will find one, beside the reference. The same 1867 to 1969 record covers pocket watches, and the number is on the movement there in the same way. Collectors on the NAWCC message board report the same number stamped on the cuvette, the inner dust cover, and on the case as well, which would save opening the movement; that is collector reporting, not a Longines statement, and the Longines Museum's own reply in that thread notes not every case is engraved.

Because that is where the sequential numbering ended. The last figure anyone publishes is 15,000,000, the start of 1969, and there is no published number for the end of that year. From about 1970 Longines serials leave the old run and commonly begin 50, and no table dates them. A chart that carried on past 15,000,000 would be inventing continuity that the numbering itself does not have, so this one stops where the evidence does.

Yes, and this is the best thing about the brand. Longines runs an Extract from the Archives service covering records back to 1867. Its own request form asks for the watch reference, the serial number and photographs, and a Longines representative replies; requests go to the heritage address. What comes back is the invoice date rather than just a year, plus the calibre and the original distributor, on Longines paper. It does not include a valuation. Longines' own customer service page prices the extract at CHF 120, limits it to timepieces more than ten years old, and gives the delivery time as four to five weeks plus shipping; older write-ups calling the service free are out of date. A separate Certificate of Authenticity, signed by the company president and issued only after a Longines watchmaker has examined the watch, costs CHF 300 and takes about three months.

The compilations disagree, so here is the disagreement rather than a single figure. The chart family this page follows states six to twelve months from 1919 onward, which would be tighter than most brands, because the published record lists those years individually rather than every few. A second compilation puts it at one to two years for anything made before 1970. Both are collector work; Longines has never published these numbers, and they are reconstructed from observed watches and archive extracts. Before 1919 the record thins out and you get a window instead. Treat the answer as a year to work from, not a figure to cite.

Because the record is dense but not complete. Where it lists consecutive years, you get a single year. Where it jumps, from 1867 to 1870 for instance, the honest answer is the window those two entries bound rather than a guess inside it.

No. The reference identifies the model and the case number identifies the case. Only the movement serial is in this table. They are frequently confused, and entering a reference will not return a date.

No. Serials are engraved on counterfeits, and a number landing in a plausible year is easy to copy. What is hard to fake is agreement between the serial, the calibre, the dial printing and the case, and that is what an expert check looks at.

That it is outside this chart. The published record ends at 15,000,000, the start of 1969, and modern Longines serials commonly begin 50, well above anything the table covers, so no year comes back. The 50 series is a real, datable sequence: a Phillips lot for a ref. 7413 chronograph prints movement number 50'648'370 and is accompanied by a Longines Extract from the Archives confirming production in 1970, so the archive does read these numbers. What does not exist is a second chart anyone has checked against dated watches. One confirmed example cannot calibrate a whole series, so a 50 series number is a job for the archive extract, not a chart.