A pre-owned Omega Seamaster Planet Ocean starts at around £2,400 to £3,300 for an older 42mm steel model, and a good current-generation 43.5mm ceramic-bezel Co-Axial sits at roughly £4,500 to £6,000 as of July 2026. Chronographs, ceramic Deep Black and gold references run higher again. These are wider open-market asking prices — a floor to judge against, not what a checked and guaranteed watch costs.
The Planet Ocean is Omega’s serious dive watch: 600m water resistance, a helium escape valve, and the orange-accented bezel that has been its signature since it launched in 2005. It sits at the tool end of the Seamaster family — the same line Omega has fitted to James Bond since 1995 — and it is one of the best-value ways into a genuine, over-built Swiss diver on the secondhand market.
What does a pre-owned Planet Ocean cost in 2026?
Price is driven by generation, size and movement. The earlier 2500-calibre pieces are the entry point; the later Co-Axial Master Chronometer models with ceramic bezels command more, and the larger 45.5mm and chronograph cases are their own sub-markets. Box, papers and a recent service all add money and make resale easier.
| Planet Ocean (pre-owned) | Typical UK asking price, July 2026 |
|---|---|
| Older 42mm steel (2500-calibre, worn, no box/papers) | £2,400 – £3,300 |
| 45.5mm steel, earlier Co-Axial | £3,000 – £4,200 |
| Current 43.5mm ceramic-bezel Co-Axial Master Chronometer | £4,500 – £6,000 |
| Planet Ocean Chronograph, steel | £3,500 – £5,500 |
| Deep Black / GMT (full ceramic) | £6,000 – £9,000 |
| Sedna gold / two-tone | £8,000 – £14,000+ |
Figures are wider open-market asking prices (Chrono24 UK, Watchfinder, WatchCharts), as of July 2026 — indicative floors, not Chrono6538’s prices. Chrono6538 sells authenticated, checked and guaranteed pieces at a premium to the bare private-market floor.
Which size and generation should you look at?
The sweet spot for most wrists is a 42mm or 43.5mm steel model. The earlier 42mm 2900.50/2500-calibre pieces are the value play — honest, robust, and cheap to service. The later Co-Axial Master Chronometer generation adds a ceramic bezel, a much stronger anti-magnetic movement and a lume-filled scale, and it is the one to buy if you want the current look and the longer service intervals.
Smaller 38mm and 39.5mm cases suit a slimmer wrist and are a quiet way to wear the model without the full 45.5mm presence. If you want a chronograph, budget a little more and accept a thicker case.
How well has the Planet Ocean held its value?
Sensibly. Omega makes the Planet Ocean in volume, so it has never carried the artificial scarcity premium of a steel Rolex diver — which means the secondhand price is honest and the depreciation from retail is gentle rather than brutal. A pre-owned example is often the smart entry to the model precisely because someone else has absorbed the first drop. This is a description of past behaviour, not investment advice; values can fall as well as rise.
What to check before you buy
Confirm the reference and dial match, check the bezel action and lume, and make sure the helium escape valve and crown screw down properly. Ask about the last service — the Co-Axial movements reward regular servicing — and look for box and papers. Over-polished lugs and aftermarket bezel inserts both dent the value.
Where to buy a pre-owned Planet Ocean
Buy a watch that has been authenticated, pressure-checked and guaranteed rather than the cheapest listing you can find. You can see the current Omega watches at Chrono6538 →, each checked and photographed in-house.
Last updated: July 2026. Prices are indicative wider-market asking prices and change with condition, configuration and availability. Not investment advice.