Omega Serial Numbers

Omega Serial Number Chart (1895 to 2010)

Movement-serial milestones from the published Omega production table (1895 to 1998), with the post-1998 points taken from collector tables that disagree with one another by a year or two. Omega did not allocate serials perfectly linearly across model lines, so a given watch can sit a few years either side of the chart. From about 2019 serials are randomized and the chart does not apply.

Where to Find Your Omega Serial Number

For nearly every Omega made before about 1990, the dating serial is engraved on the movement — on a bridge or plate — so the caseback has to come off to read it. Have a watchmaker open it if you're not equipped to, both to avoid scratches and to preserve water resistance.

From about the early 1990s Omega began repeating the serial on the outside of the watch: on the underside of a lug (the lug at 7 o'clock on a Speedmaster), between the lugs, or on the outer caseback. The rollout was not uniform, so a 1990s Omega with no external number is not suspect on that account. Recent models with display backs show it on the movement through the sapphire. The serial is also printed on the warranty card or plastic certificate.

Don't confuse the serial with the reference (model) number, which on vintage pieces is stamped inside the caseback and identifies case style, size, and metal.

Where to look, line by line:

• Speedmaster Professional (hand-wound cal. 321, 861, 1861): the serial is engraved on the movement, on a bridge or plate whose position varies by caliber. The screw-down caseback carries the Seahorse and, from about 1970, the moon-landing inscription; the reference (ST 105.012, ST 145.022 and so on) is stamped on its inside.
• Seamaster and Constellation (automatic): serial on the rotor bridge or a plate under the rotor. Constellation casebacks carry the observatory medallion outside and the reference inside.
• Quartz and 1990s pieces: check the outer caseback and the underside of the lugs first. Some quartz calibers carry no serial on the movement at all, so the case engraving is the number to use.
• Modern Omega: an eight-digit serial engraved on the caseback or a lug, sometimes visible on the movement through a display back, and printed on the warranty card. Watches from the 2010s mostly carry numbers in the 80 and 90 millions; from about 2019 the eight digits are randomized. Recent cards can also show a seven-character alphanumeric number.

How to Read an Omega Serial Number

Omega serials from the 1890s through the 1990s are 7- or 8-digit numbers issued broadly in chronological order. There is no embedded year code — no single digit tells you the year — so dating means matching the full number to a production-year chart.

Useful anchors: 1 million is 1895, 10 million is 1944, 20 million is 1963, the mid-20 millions are the late 1960s (the classic cal. 321 Speedmaster era), 44 million is 1980 and 53 million is 1990. Omega's published table stops at 58 million in 1998; the points after that come from collector tables that disagree with one another by a year or two.

Two things the chart cannot do. It dates the movement, not the sale: Omega cased and sold movements months and sometimes years after they were numbered, so a 1968 serial in a watch sold in 1970 is normal. And it cannot tell one model from another: the same serial block was shared across every line Omega made that year.

After 1998 the sequence kept climbing: the 60 millions around 1999 to 2000, the 70 millions in the mid-2000s, the 80 millions in the second half of the 2000s and the 90 millions from about 2010. Around 2019, with the count approaching 100 million, Omega stopped issuing serials in order and moved to randomized eight-digit numbers, so a recent Omega is dated from its warranty card, not from a chart.

Caliber and Reference Numbers

The caliber number identifies the movement design — cal. 321, 861, and 1861 for the Speedmaster across eras, for instance — and is stamped on the movement itself. Many different watches can share one caliber.

The reference (or PIC, Product Identification Code) describes the case and configuration. Vintage references are numeric and stamped inside the caseback; modern Omega uses a structured code primarily recorded on the card and Omega's documentation rather than engraved in full.

Omega Serial Numbers by Model Line

Because Omega numbered movements in one shared sequence, the serial alone will not tell you which model you are holding. Read it together with the reference inside the caseback and the caliber stamped on the movement. The pairings below are the ones buyers most often need to check.

• Speedmaster Professional, cal. 321: reference 105.003 with serials from about 20.5 to 25.4 million (1963 to 1965), 105.012 from about 20.5 to 25.5 million (1964 to 1968) and 145.012 from about 24 to 28 million (1967 to 1968), per the Speedmaster101 and SpeedyBase registries. The references overlap, so read the serial with the case. A cal. 321 serial in the 30 millions is a replacement movement or a later service assembly.
• Speedmaster Professional, cal. 861 (from 1968): reference 145.022, in production to 1988 (written 145.0022 from about 1981), with serials from about 26.5 million (the 145.022-68) through the 27 to 31 millions for the 145.022-69 and on into the 40 millions through the 1970s and 1980s. Cal. 1861 replaced it in 1996.
• Seamaster 300: reference 165.024 (no date, cal. 552) and 166.024 (date, cal. 565), serials from the low 20 millions into the low 30 millions (1964 to 1969).
• Constellation pie-pan: reference 167.005 (no date, cal. 551) and 168.005 (date, cal. 561, then the quick-set cal. 564 from 1966), serials from the high teens of millions through the 20 millions (about 1962 to 1970).
• A serial well outside the window for its reference is the single most useful franken tell on a vintage Omega: it means the movement and the case did not leave the factory together.

Is Your Omega Real? What the Serial Can and Cannot Tell You

A serial that decodes to a plausible year proves very little on its own. Counterfeiters copy real numbers, and the number is only on the movement, which a listing photo may not show. What the serial does give you is a consistency check, and consistency is where fakes and frankens fail.

Ask for a photograph of the movement with the caseback off. On a genuine vintage Omega the serial is machine-engraved, even and shallow, on a bridge or plate; the caliber number sits nearby; and the word OMEGA and the jewel count are engraved in the same hand. A serial that is deeper, wobblier or in a different typeface from the other engraving has been added. Then check three things against each other: the serial's year, the reference stamped inside the caseback, and the caliber. All three should belong to the same few years and the same model line, using the pairings above. A cal. 861 in a 105.012 case, or a 1972 serial in a Seamaster 300 reference that ended in 1969, is a marriage of parts rather than a counterfeit, and it should be priced as one.

The dial is the other half of the check, and the serial cannot help you there: redials and service dials are the commonest problem on vintage Omega, and they carry no number. The step that settles everything is the same as for any watch: a watchmaker who knows the caliber, or an Extract from the Archives, which confirms the caliber, the reference and the delivery date the factory recorded for that serial (it describes how the watch left Biel, not whether every part is still original; Omega's separate Certificate of Authenticity does that, and requires the watch to be sent in). Our guide to spotting a frankenwatch covers the dial side; every Omega sold on Grey Market goes through that inspection before the seller is paid.

What the Serial Says About Value

The year matters to price because it sorts a reference into its collectible generations. On the Speedmaster, a cal. 321 serial in a 105.012 case is worth several times a cal. 861 serial in a 145.022 case that looks almost identical across a room. On the Seamaster 300, the 165.024 serials before about 1968 carry the earlier dial and bezel details collectors pay for. On the Constellation, the pie-pan dial pieces of the late 1950s and early 1960s command more than the later C-shape cases.

Once you have the year and the reference, the reference guides on this site show what each one has actually sold for, banded from recent dealer, auction and Grey Market results, and our price history covers the references we track. If the watch is one you might sell, the year and reference are the two facts a buyer will ask for first.

Frequently asked questions