Omega Seamaster De Ville
A dress Seamaster in a slim one-piece case, made from 1960 until the De Ville became its own line around 1967. Two names on one dial dates the watch to that window before you've read a single number. Here is how to identify one, what's inside it, and what it's worth.
What it is
Omega launched the Seamaster De Ville in 1960 as the town version of the Seamaster: same movements, but a thinner case with no screw-down back, a flat or gently domed crystal, and a plainer dial. The case is the thing to know. It is a monocoque — the back and the case middle are one piece of metal — so there is no caseback to unscrew. The crystal comes off with a lift tool, the crown and stem are released, and the movement comes out through the front. Anyone attacking the back of one with a caseback wrench is about to scar a watch that was never designed to open that way.
In 1967 Omega made De Ville a line of its own and the Seamaster name came off the dial. So the two-name dial is a period marker: Seamaster De Ville is 1960–67; De Ville alone is 1967 onward. Expect exceptions at the boundary — Omega used up dials — but a "Seamaster De Ville" with a 1970s calibre inside is a watch to look at twice.
How to identify one
- Dial: "Seamaster" and "De Ville" on separate lines below the Ω and OMEGA, usually with "Automatic" if it is one. Applied hour markers, dauphine or baton hands, a dial that is silvered, sometimes cross-hatched or with a subtle texture. Early dials say SWISS MADE; from the mid-1960s the tritium marks T SWISS MADE T appear.
- Back: flat, with the Seamaster seahorse in relief on many examples, and no visible seam for a caseback — that seam is the tell for a one-piece case. Some late or ladies' examples have conventional snap or screw backs; the reference decides.
- Reference: stamped inside the case, which on a monocoque means you see it only with the movement out. The classic references are 166.020 (automatic, date), 165.020 (automatic, no date), 135.020 (hand-wound) and 136.020 (hand-wound, date), prefixed by the material code — ST for steel, MD for gold-plated, BA for 18k gold.
- Movement: the calibre number is on the rotor bridge or the plate. 552 is the 24-jewel no-date automatic; 560 (17 j), 562 and 565 (24 j) are the date versions, 565 with quick-set from 1966. Hand-wound versions are the 600 family. Date the serial — it should sit in the 1960s.
Reference to calibre, from Omega's own parts data
These pairings come from Omega's case bills of materials as they stood in 2012 — the parts system, not a forum. A Seamaster De Ville reference with a different calibre inside than the ones listed here has had its movement changed.
| Case reference | Calibres Omega lists for it | What that means |
|---|---|---|
| 166.0020 | 560, 562, 565 | Automatic with date. 560 = 17 jewels; 562 and 565 = 24 jewels; 565 has quick-set date. |
| 165.0003 · 165.0023 · 165.0024 | 552 | Automatic, no date, 24 jewels. 165.020 (the classic no-date Seamaster De Ville) uses the same 552. |
| 135.0020 | 600 | Hand-wound, no date, 17 jewels. |
| 136.0017 | 610, 611 | Hand-wound with date. |
| 111.0024 · 111.0133 · 111.0136 | 620 · 625 | Ladies' hand-wound Seamaster De Ville / De Ville cases. |
The Movement ID report checks your specific reference against this data and the original GF 620 catalogues, which is what settles a marriage question in writing.
Dating one
The reference format is the first clue: the three-digit-point-four-digit style (166.020) came in around 1962–63; earlier Seamaster De Villes carry the older style like 14910 or 14920. The dial's "Swiss Made" line is the second: no T marks means earlier 1960s, T SWISS MADE T means tritium and mid-1960s on. The serial is the third and the sharpest — run it through the serial lookup and the year band should land between 1960 and 1967, with the calibre appearing in that band's list.
What it's worth
In 2026 a steel Seamaster De Ville with an original dial, running well, sells in the high hundreds to low thousands of US dollars, with 565-date automatics and cleaner dials at the top of the range. Gold-capped ("MD") examples are similar to steel unless the cap is worn through at the lugs, which is common and drops them. Solid gold examples are priced by the case as well as the watch — check for the fineness stamp before assuming either way. Redials and non-runners sell for roughly half as watches; as parts the 552/565 movement, the seahorse case and an original dial each hold their value on their own. How the three values work.
What goes wrong with them
- Scarred cases from attempts to open the non-existent caseback. Look at the flat back for pry marks and gouges at the edge.
- Redials. Very common; the plain silvered dial is easy to refinish and hard to refinish well. Compare the printing against a known original; the Ω and the text weight give it away.
- Worn gold cap on MD cases: base metal showing at the lug tips and case edges.
- Married movements. A 1970s 1010/1012 in a 166.020 case is not original — the reference table above is the check.
- Replaced crowns and crystals — normal for a serviced 60-year-old watch, not a reason to walk away, but note it. Full authentication checklist.
Not sure what you have? Photos of the dial, the back, the movement if you can get to it, and the watch on a kitchen scale in grams, to id@watchbreaker.com with the subject "What is it?" — calibre, age band, metal and a value verdict, free, normally within a day. For a written Movement ID report citing the catalogue references (US$25, sample), use the subject "Movement ID request". I never take custody of your watch.
Questions people ask
What years was the Omega Seamaster De Ville made?
1960 until about 1967, when De Ville became a line of its own. A dial that reads both Seamaster and De Ville is a 1960s watch.
What movement is in an Omega Seamaster De Ville?
Automatics: calibre 552 (no date) or 560, 562, 565 (date). Hand-wound: 600 or 601 (no date), 610, 611, 613 (date). Omega's parts data lists 560/562/565 for reference 166.0020 and 600 for 135.0020.
How do you open an Omega Seamaster De Ville?
From the front. The one-piece case has no removable back; the crystal lifts off with a crystal lift or compressor tool, the stem is released, and the movement comes out through the front.
Is the Seamaster De Ville waterproof?
It was sold as water-resistant to a modest degree when new — the monocoque case is actually a good seal — but a 60-year-old gasket and a lifted crystal are not. Treat it as splash-resistant at best.
How much is an Omega Seamaster De Ville worth?
Steel with an original dial and running: high hundreds to low thousands of US dollars. Redials and non-runners roughly half. Solid gold priced by the case as well.
Watch Breaker is an independent identification specialist and parts dealer and is not affiliated with, endorsed by or connected to Omega SA or the Swatch Group. Omega, Seamaster and De Ville are trademarks of Omega SA. Reference-to-calibre data is taken from Omega case parts lists as published in 2012; part numbers are facts and no catalogue pages are reproduced. Terms.