Omega Seamaster Guide: Diver 300M, Aqua Terra, Planet Ocean, Seamaster 300, Ploprof and Railmaster

The Omega Seamaster is not one watch but a family that has carried the name since 1948, when Omega marked its centenary with a water-resistant dress watch, and that now spans six distinct lines. The Seamaster Diver 300M is the 42 mm ceramic-dial diver that James Bond has worn since 1995, running the Master Chronometer calibre 8800; the Aqua Terra 150M is the everyday watch in 38 mm and 41 mm with the calibre 8800 and 8900; the Planet Ocean 600M is the heavier professional diver in 39.5 mm and 43.5 mm plus a 45.5 mm chronograph; the Seamaster 300 is the 41 mm heritage diver on the no-date calibre 8912; the Ploprof 1200M is the 55 mm saturation-diving instrument; and the Railmaster is the anti-magnetic field watch, relaunched in 38 mm in 2025. This guide explains how the families differ in case size, water resistance, movement and certification, which references exist and what they asked on October 26, 2026, how each compares with the Rolex Submariner, Sea-Dweller and the Tudor Black Bay, and what to check when buying one pre-owned. Bizak & Co. sources every Seamaster to order; the Seamaster collection lists the references we can seek.

Last reviewed on October 26, 2026 by Filip Biczak. Prices are dated observations, not quotes.

Omega Seamaster families compared: sizes, water resistance and calibres

Source: the specifications above were read on Omega's own Seamaster pages and matched against the Bizak catalogue titles. Every current Seamaster calibre is Master Chronometer certified, which means the cased-up watch is tested by the Swiss federal metrology institute, METAS, for accuracy between zero and plus five seconds a day, for resistance to magnetic fields of 15,000 gauss, for power reserve and for water resistance. That sits above the classic chronometer certificate issued on bare movements by the COSC, which is the standard that the previous-generation calibres 2500 and 8500 carry. The Swiss made label on every Seamaster is defined by the watch industry's federation, the FH.

Which Omega Seamaster references exist, and what do they ask?

The table lists the Seamaster references Bizak's sourced catalogue carried on October 26, 2026, all sourced to order and all brand new unless the listing says pre-owned. It is a selection from more than six hundred Seamaster listings across the Seamaster collection; the dial and bracelet variants not shown here follow the same pricing pattern as their siblings. Every figure is a dated ask that will move.

Omega's reference system reads from left to right: the first group is the family and generation (210 for the current Diver 300M, 212 for the previous one, 220 for the 2017 Aqua Terra and Railmaster, 231 for the previous Aqua Terra, 215 for the 2016 Planet Ocean, 232 for the 2011 Planet Ocean, 233 and 234 for the two Seamaster 300 generations, 224 and 227 for the Ploprof, 235 for the 2025 Railmaster, 522 for Olympic editions), the second the material and bracelet (30 steel on steel, 32 steel on rubber or NATO, 33 steel on leather, 20 and 22 steel and gold, 60 and 62 gold, 90 and 92 titanium or Bronze Gold, 55 and 58 gem-set), then the case size, the movement family, a dial code (01 black, 02 silver, 03 blue, 04 white, 06 grey, 10 green, 13 brown) and a sequence number. The Omega collection holds the wider catalogue, including the Speedmaster and Constellation lines, and the steel Aqua Terra collection gathers that family on its own.

Seamaster Diver 300M: the 42 mm 210.30 and 210.32, the chronograph and the Bond editions

The Diver 300M arrived in 1993 as a 41 mm steel diver with a wave-pattern dial, a scalloped bezel, skeleton hands and a helium escape valve at 10 o'clock, and it became the best known Seamaster when Pierce Brosnan wore the blue quartz 2541.80 in GoldenEye in 1995 and the automatic 2531.80 from Tomorrow Never Dies onwards. The second generation of 2012, the 212.30.41.20.xx series, kept the 41 mm case and the calibre 2500 Co-Axial chronometer and added a ceramic bezel insert; Bizak's catalogue listed the blue 212.30.41.20.03.001 at US$4,399 and the black 212.30.41.20.01.002 at US$4,166 on October 26, 2026, sourced to order, which makes the previous generation the least expensive route into a Bond Seamaster with a modern escapement.

The current generation was launched in 2018 and is the watch most buyers mean by Seamaster. The case grew to 42 mm, the dial became laser-engraved ceramic with the waves cut into it, the bezel insert ceramic with a white enamel or Ceragold diving scale, the helium valve conical, and the case back a sapphire window. Behind it sits the calibre 8800: a Co-Axial escapement, a silicon balance spring, 25,200 vibrations an hour, about 55 hours of power reserve and Master Chronometer certification. The steel watch comes as the 210.30.42.20.xx.001 on the bracelet and the 210.32.42.20.xx.001 on the rubber strap, with black, blue, grey, green and white dials; on October 26, 2026 the catalogue asked US$5,699 for the black 210.30.42.20.01.001, US$4,818 for the blue 210.30.42.20.03.001 and US$5,355 for either colour on rubber, sourced to order. The white dial 210.30.42.20.04.001 asked US$6,305 and the grey and green bracelet watches US$5,695. Two-tone versions in steel with Sedna or yellow gold use the same calibre; the full gold watches use the 8801 with a gold rotor and balance bridge.

The chronograph is a 44 mm watch, not a 43.5 mm one as it is sometimes described: the 210.30.44.51.xx.001 carries the column-wheel calibre 9900 with twin barrels, 60 hours of reserve and two sub-dials, and on October 26, 2026 the catalogue listed the black 210.30.44.51.01.001 at US$7,999, the blue 210.30.44.51.03.001 at US$8,160 and the black on rubber 210.32.44.51.01.001 at US$7,820, sourced to order. The earlier 212.30.44.50 chronograph of 2012 used the calibre 3330 and the 2225.80.00 of the 1990s and 2000s the 3313; both are listed in the four thousands.

The Bond and anniversary editions are the Diver 300M's most sought-after references. The 007 Edition 210.90.42.20.01.001 was built for No Time to Die with Daniel Craig's input: a 42 mm grade 2 titanium case, a brown tropical dial and bezel, a no-date calibre 8806, a mesh bracelet or a striped NATO (210.92.42.20.01.001), and a case back engraved with military-style markings. It is not a limited edition, which has kept its asks near list; Bizak listed the mesh at US$9,605 and the NATO at US$8,599 on October 26, 2026. The James Bond 60th Anniversary 210.30.42.20.03.002 of 2022 pairs a blue dial and bezel with a no-date calibre 8806 and a case back whose animation reproduces the gun-barrel sequence; the catalogue asked US$8,100 for it, and US$160,140 for the Canopus gold 210.55.42.20.99.001. The 2023 watch in titanium with a tantalum and Sedna gold bezel and bracelet links, the 210.60.42.20.99.001, revives the three-metal look of the 1990s Seamaster and asked US$14,620; the Nekton Edition 210.30.42.20.01.002, with a laser-engraved black ceramic dial and a case back marked for the Nekton deep-ocean research mission, asked US$6,800. The Bronze Gold 210.92.42.20.01.003, in Omega's own bronze alloy that does not form a green patina, asked US$14,110 on rubber. All dated October 26, 2026 and sourced to order.

Seamaster Aqua Terra 150M: 38 mm and 41 mm, calibre 8800 and 8900, small seconds and Worldtimer

The Aqua Terra was introduced in 2002 as the Seamaster for people who swim rather than dive: 150 m of water resistance, a screw-in crown, no rotating bezel and no helium valve, and a dial clean enough to wear with a suit. The 2008 generation (231.10.42.21) brought the teak-deck dial with vertical stripes and the calibre 8500, the first of Omega's in-house Co-Axial calibres, COSC certified and later joined by the 8508 in the 2013 "15,000 Gauss" watch, which proved the anti-magnetic technology that became the Master Chronometer standard. Those 41.5 mm and 38.5 mm watches are still listed: the black 231.10.42.21.01.002 at US$5,399, the 15,000 Gauss 231.12.42.21.01.001 at US$5,299, the Day-Date 231.10.42.22.03.001 with the calibre 8602 at US$6,199 and the Annual Calendar 231.10.39.22.03.001 with the calibre 8601 at US$6,699, all on October 26, 2026 and sourced to order.

The current generation of 2017 (220.xx) turned the teak stripes horizontal, moved the date to 6 o'clock, made the case symmetrical with a conical crown, slimmed the lugs and gave the watches new calibres: the 8900 in the 41 mm, with twin barrels, about 60 hours of reserve and an independently adjustable hour hand for changing time zones, and the 8800 in the 38 mm, with about 55 hours. Both are Master Chronometer. On October 26, 2026 Bizak's catalogue listed the 41 mm blue 220.10.41.21.03.001 at US$5,615, the black 220.10.41.21.01.001 and green 220.10.41.21.10.001 at US$6,035, the silver 220.10.41.21.02.001 at US$5,999 and the blue on rubber 220.12.41.21.03.001 at US$5,350; the 38 mm black 220.10.38.20.01.001 asked US$6,035, the blue 220.10.38.20.03.003 US$6,299 and the green 220.10.38.20.10.002 US$6,290, all sourced to order. The 2022 Shades series added lacquered dials in colours from sandstone to terracotta in 38 mm and 34 mm, and the 2023 expansion brought the colours to 41 mm; the 34 mm white sandstone 220.10.34.20.09.001 asked US$6,290.

Two complications sit inside the family. The Small Seconds of 2022 moves the seconds to a sub-dial at 6 o'clock with the date inside it, on the calibre 8916 in 41 mm and the 8802 in 38 mm; the 41 mm silver 220.10.41.21.02.002 asked US$6,399 on October 26, 2026. The Worldtimer, launched in Sedna gold in 2017 and in steel in 2020, is a 43 mm watch with a 24-hour ring and a laser-ablated titanium world map at the centre of the dial, driven by the calibre 8938 with the 8939 in gold; the steel blue 220.10.43.22.03.001 asked US$9,499, the rubber-strap 220.12.43.22.03.001 US$9,265 and the Sedna gold 220.50.43.22.02.001 on a gold bracelet US$48,365. The two-tone 41 mm 220.20.41.21.02.001 asked US$12,699 and the Moonshine gold green-dial 220.52.41.21.10.001 US$22,525, all sourced to order. The Aqua Terra is the Seamaster to buy when one watch has to cover the office, the beach and a dinner; the Which Omega to buy guide puts it against the Speedmaster and Constellation.

Seamaster Planet Ocean 600M: 39.5 mm, 43.5 mm, chronograph, GMT and Ultra Deep

The Planet Ocean was launched in 2005 as a heavier, deeper diver than the 300M, rated to 600 m with a helium valve, broad arrow hands and an orange accent, in 42 mm and 45.5 mm on the calibre 2500; Daniel Craig wore the 45.5 mm in Casino Royale and the 42 mm in Quantum of Solace and Skyfall. The 2011 generation (232.xx) brought the calibre 8500 with a sapphire display back, a ceramic bezel and a 37.5 mm size on the calibre 8520; the black 232.30.42.21.01.001 and the 45.5 mm 232.30.46.21.01.001 each asked US$6,199 on October 26, 2026, sourced to order, which makes a COSC-certified in-house Planet Ocean one of the better values in the catalogue.

The current generation of 2016 (215.xx) resized the three-hand watches to 39.5 mm on the calibre 8800 and 43.5 mm on the calibre 8900, both Master Chronometer, with a ceramic bezel whose scale is in Liquidmetal or Ceragold, a ceramic dial on many versions and a rubber-lined leather strap as an alternative to the bracelet. The 39.5 mm is the Planet Ocean for most wrists: on October 26, 2026 the catalogue listed the black 215.30.40.20.01.001 at US$6,785, the blue 215.30.40.20.03.001 and white 215.30.40.20.04.001 at US$6,800 and the black on strap 215.33.40.20.01.001 at US$5,899. The 43.5 mm wears closer to the original: the black 215.30.44.21.01.001 asked US$6,199, the blue 215.30.44.21.03.001 US$6,800, the black on rubber 215.32.44.21.01.001 US$6,460 and the titanium 215.90.44.21.99.001 US$7,755, sourced to order.

The complications are where the Planet Ocean separates itself from the Diver 300M. The GMT 215.30.44.22.01.001, 43.5 mm on the calibre 8906 with a 24-hour bezel and hand, asked US$8,330 on October 26, 2026. The chronograph is 45.5 mm on the column-wheel calibre 9900: the black 215.30.46.51.01.001 asked US$8,755 and the blue 215.30.46.51.03.001 US$8,999. The Deep Black of 2016 is a 45.5 mm GMT machined entirely from ceramic, the 215.92.46.22.01.006 asking US$15,758. The Ultra Deep of 2022 is the production version of the watch that went to the bottom of the Mariana Trench in 2019: 45.5 mm, rated to 6,000 m, in Omega's O-MEGASTEEL alloy on the calibre 8912, with the gradient blue 215.30.46.21.03.001 at US$10,498 and the gradient grey 215.30.46.21.06.001 at US$11,599, all sourced to order. A Planet Ocean is the Seamaster to buy for the depth rating, the GMT or the chronograph; it is also the one that most needs trying on, because the 43.5 mm and 45.5 mm watches are thick.

Seamaster 300 heritage: the 2014 watch, the Spectre edition and the 2021 calibre 8912

The Seamaster 300 of 1957 was one of Omega's three professional watches of that year with the Speedmaster and the Railmaster, a 300 m diver with broad arrow hands and a black bezel, and it is the design the modern Seamaster 300 revives. The 2014 watch (233.30.41.21.01.001) brought it back at 41 mm with a sandwich dial in which the lume shows through cut-outs, a Liquidmetal bezel and the calibre 8400, Omega's first Master Co-Axial movement resistant to 15,000 gauss, which preceded METAS certification; Bizak's catalogue asked US$5,249 for it on October 26, 2026, sourced to order. The Spectre edition of 2015 (233.32.41.21.01.001) changed the bezel to a bidirectional 12-hour scale, added a lollipop seconds hand and a striped NATO, was limited to 7,007 pieces and asked US$10,199. The 2017 Trilogy editions reissued all three 1957 watches in 39 mm and 38 mm cases with a calibre 8806 and a limited run of 3,557 each, with 557 complete sets; the set-edition Seamaster 300 234.10.39.20.01.002 asked US$20,099.

The current Seamaster 300 of 2021 (234.30.41.21.xx) is slimmer and more faithful to 1957. The dial is an open sandwich with the lume in a cream, old-radium tone, the bezel insert is anodised aluminium rather than ceramic, the hands are broad arrows, there is no date and the movement is the calibre 8912, a no-date Master Chronometer with about 60 hours of reserve. On October 26, 2026 the catalogue listed the black 234.30.41.21.01.001 at US$6,800, the blue 234.30.41.21.03.001 also at US$6,800, the black on leather 234.32.41.21.01.001 at US$6,460, the Summer Blue 75th anniversary 234.30.41.21.03.002 at US$7,055 and the Bronze Gold 234.92.41.21.10.001 at US$13,345, sourced to order. The Seamaster 300 is the Seamaster for a buyer who wants a vintage-styled diver that is still rated to 300 m and will keep time to Master Chronometer tolerances, and it is the closest Omega to a Tudor Black Bay in spirit.

Ploprof 1200M and Railmaster: the specialist Seamasters

The Ploprof, from the French "plongeur professionnel", was Omega's 1970 answer to saturation diving: a monobloc case so thick that it needed no helium valve, a crown on the left, a bezel that locks until the orange pusher at 2 o'clock is pressed and a rating of 600 m. Omega reissued it in 2009 as the Ploprof 1200M in steel on the calibre 8500 (224.30 and 224.32, the latter on rubber), then in 2015 as a titanium watch on the Master Chronometer calibre 8912 with a sapphire display back, a ceramic bezel and a helium valve, rated to 1,200 m (227.90.55.21.xx). In 2023 the Summer Blue edition brought the Ploprof back in O-MEGASTEEL (227.32.55.21.03.001). On October 26, 2026 Bizak's catalogue listed the titanium black 227.90.55.21.01.001 at US$10,699, the titanium grey 227.90.55.21.99.001 at US$12,499, the O-MEGASTEEL Summer Blue at US$13,685 and the 2009-generation steel 224.32.55.21.01.001 on rubber at US$7,099, sourced to order. It is a 55 mm by 48 mm watch and it is as heavy as that suggests; buyers choose it because nothing else in the catalogue looks like it.

The Railmaster of 1957 was built for railway workers and scientists who worked near strong magnetic fields, with a soft-iron inner case rated to 1,000 gauss. The 2017 relaunch (220.10.40.20.01.001) made it a 40 mm field watch with a vertically brushed dial, no date and the calibre 8806, resistant to 15,000 gauss without any inner case, alongside the 38 mm Trilogy edition (220.10.38.20.01.002, 3,557 pieces). In 2025 Omega replaced it with a 38 mm Railmaster with a small seconds display at 6 o'clock on the calibre 8804, in grey (235.10.38.20.06.001) and brown (235.12.38.20.13.001). The catalogue asked US$5,099 for the 40 mm black on bracelet, US$4,899 on the fabric strap, US$5,199 for the 2025 grey, US$5,499 for the 2025 brown on leather and US$6,499 for the Trilogy, all on October 26, 2026 and sourced to order. The Railmaster is the Seamaster for a buyer who wants the Aqua Terra's wearability with a plainer, tool-watch dial.

What changed in the Omega Seamaster catalogue in 2025 and 2026?

Three changes can be confirmed from Omega's own pages and from the Bizak catalogue titles. The first is the Railmaster: the 2017 40 mm watch has been superseded by the 2025 38 mm small-seconds watch on the calibre 8804, though the 40 mm remains in Bizak's sourced listings. The second is the 2026 Winter Olympics edition: the Seamaster 37 mm "Milano Cortina 2026" 522.53.37.20.04.001 in Moonshine gold with a white dial, which continues the 522 Olympic reference series that includes Rio 2016, Pyeongchang 2018, Beijing 2022 and Paris 2024, and which asked US$19,550 on October 26, 2026, sourced to order. The third is a run of new Diver 300M dial variants with high sequence numbers, such as the 210.30.42.20.01.010 and the black and orange 210.30.42.20.01.018, both listed at US$6,205; those sequence numbers indicate later dial releases within the current generation rather than a new case or movement.

What has not changed matters as much. The Diver 300M, Aqua Terra 41, Planet Ocean 39.5 and 43.5 and Seamaster 300 all remain on the 8800, 8900 and 8912 calibres introduced between 2016 and 2021, so a watch bought in 2019 is mechanically the same as one bought in 2026, which keeps pre-owned values close to the new asks. The 2023 Summer Blue series, eleven watches with gradient blue dials across every family to mark the Seamaster's 75th anniversary, remains in the catalogue as a regular range, with the Diver 300M at US$6,199, the Seamaster 300 at US$7,055 and the Planet Ocean 39.5 mm 215.30.40.20.03.002 at US$7,055 on October 26, 2026.

Which Omega Seamaster should you buy, and how do they wear?

The Diver 300M at 42 mm is about 13.5 mm thick and roughly 50 mm from lug to lug, with 20 mm lugs and a bracelet that tapers to a fold-over clasp with a diver's extension. It wears large for its size because the dial is open and the bezel thin, and it suits wrists from about 16.5 cm (6.5 inches); the skeleton hands and wave dial make it a sporty watch that still passes under a cuff. The Aqua Terra 41 is about 13 mm thick and 48 mm lug to lug with the same 20 mm lug width, and because it has no bezel it looks smaller than the Diver; the 38 mm, at about 12 mm thick and 45 mm lug to lug on 19 mm lugs, is the Seamaster for a wrist under 16.5 cm or for anyone who prefers a mid-size watch, and the 34 mm is sized for small wrists. The Planet Ocean 39.5 is about 14 mm thick and wears like a compact tool watch; the 43.5 mm is nearer 16 mm thick and the 45.5 mm chronograph thicker still, so both ask for a wrist above 18 cm (7 inches) or a tolerance for a tall watch. The Seamaster 300 is about 14 mm thick at 41 mm with a flat-link bracelet that sits close to the wrist, and the Railmaster 38 is the slimmest of the group. The Ploprof needs no measurement; it either suits you or it does not.

In practice the choice runs like this. A first Omega or a single sports watch: the Diver 300M in steel, blue or black, on the bracelet, with a rubber strap bought later. A watch for the office that will also swim: the Aqua Terra 41 or 38. A watch for actual diving, travel or a chronograph: the Planet Ocean 39.5, GMT or chronograph. A vintage look with modern tolerances: the Seamaster 300. A conversation piece: the Ploprof or the titanium 007. The Speedmaster Moonwatch guide covers the other half of a two-Omega collection.

Omega Seamaster vs Rolex Submariner, Sea-Dweller and Tudor Black Bay

The Submariner wins on finishing, on the Glidelock clasp and on the tighter accuracy tolerance, and it keeps its value because supply is controlled; the Diver 300M wins on price, on the display back, on magnetic resistance and on being available without a waiting list. The Submariner vs Sea-Dweller guide explains why the Sea-Dweller's depth rating costs so much more; against the Seamaster, the Planet Ocean 600M and the Ultra Deep are the closer rivals to the Sea-Dweller, and the Planet Ocean 43.5 mm gives twice the depth rating of a Submariner with a display back for roughly half the money. The Tudor Black Bay 58 is the Seamaster 300's natural rival: smaller, thinner and cheaper, with a COSC movement rather than a Master Chronometer, although Tudor's own Master Chronometer calibres have been spreading through the Black Bay range since 2021. The Tudor Pelagos, in titanium and rated to 500 m, sits between the Diver 300M and the Planet Ocean on depth and price. The Submariner collection shows the Rolex asks for comparison.

How much is an Omega Seamaster? Retail and dealer prices in 2026

• Retail. Omega's US list price for the steel Diver 300M on the bracelet has sat a little above US$6,000 in recent years, with the rubber-strap version a few hundred dollars less and the chronograph in the low nine thousands; the Aqua Terra 41 and 38 in steel list in the high six thousands, the Planet Ocean 39.5 and 43.5 in the high six to low seven thousands, the Seamaster 300 in the high six thousands, the titanium Ploprof in the low teens of thousands and the gold watches from the high twenties upwards. Omega has raised list prices more than once since 2021; the current figures are on Omega's product pages and in its boutiques.
• Secondary market. Through 2025 and 2026 the steel Seamasters have traded below list rather than above it. Unworn full-set Diver 300M watches have generally been asked ten to twenty per cent below list, pre-owned examples lower, and previous-generation 212.30.41 watches in the low four thousands. The exceptions are the limited and themed editions: the Spectre Seamaster 300, the Trilogy watches and the Canopus gold 60th Anniversary ask above their original list, and the titanium 007 Edition holds close to list because demand has stayed steady. Gold Seamasters, as gold Omegas usually do, trade well below list on the secondary market. Auction results for vintage Seamaster 300s and Ploprofs are published by Sotheby's watch department.
• Bizak catalogue asks. On October 26, 2026 our sourced catalogue listed the blue Diver 300M on the bracelet at US$4,818 and the black at US$5,699, the Aqua Terra 41 blue at US$5,615, the Planet Ocean 39.5 black at US$6,785, the Seamaster 300 black at US$6,800, the 007 Edition titanium at US$9,605 and the titanium Ploprof at US$10,699, all sourced to order.

Those figures describe what we saw that day and will move. Ask for a dated quote for the exact reference, year and card. Where a Seamaster ask is far below the others, as with the blue Diver 300M above, confirm the generation, whether the card is dated and whether the bracelet and the full strap kit are present before reading anything into the number.

Is the Omega Seamaster a good buy?

As a watch to own, the Seamaster is one of the strongest cases in its price band. Every current reference is a Master Chronometer with a silicon balance spring and resistance to 15,000 gauss, which means it will keep its timekeeping in a life full of phone cases and laptop lids; Omega backs new watches with a five-year warranty; its service network handles every Seamaster calibre; and the range is wide enough that a buyer can choose by size, depth rating and complication rather than take what the retailer allocates. The Diver 300M in particular offers a ceramic dial and bezel, a display back and a column of film history for less than the secondary price of a Submariner. As an investment the steel Seamasters are steady rather than exciting: they trade below list, so a new watch loses some value on the day it is bought and then holds, and the money is in buying a clean pre-owned example rather than hoping for appreciation. The limited editions are where values have risen, and the pre-owned collection shows how we describe those.

Buying a used Omega Seamaster: what to check

• Generation and reference. The reference is engraved on the case back or between the lugs. A 210 prefix is the 2018 ceramic-dial Diver 300M on the calibre 8800; a 212 is the 2012 watch on the calibre 2500 with a ceramic bezel; a 2531 or 2220 is the 1990s and 2000s watch on the calibre 1120 or 2500 with an aluminium bezel and a lacquered wave dial. The price difference between them is large, so match the reference to the ask.
• Warranty card. Omega has issued a five-year international warranty since 2018, with a card or a digital record carrying the reference, the serial and the retailer's stamp. Match the serial on the card to the engraving on the case; a Master Chronometer watch also comes with a card bearing the METAS certificate number, which can be checked against Omega's records.
• Ceramic dial and bezel. Ceramic does not scratch in normal wear, so a chipped bezel edge or a mark on the dial means an impact; check the bezel at 12 o'clock where the lume pip sits and look across the dial under a raking light. On aluminium-bezel Seamaster 300s and 1990s Diver 300Ms, fading and scratches are normal and a replaced insert changes the value.
• Helium escape valve. On a Diver 300M or Planet Ocean, unscrew the valve at 10 o'clock and screw it back: it should turn smoothly and seat firmly. A valve left open compromises water resistance, so ask when the watch was last pressure tested.
• Crown and date. The crown should screw down with firm resistance and the date should jump at midnight on the 8800 and 8900, with the 8900's hour hand moving independently in the first crown position. A date that changes slowly or a crown that spins without engaging means a service.
• Bracelet and clasp. The Diver 300M clasp has a diver's extension and the Planet Ocean and Aqua Terra clasps a fine adjustment; check that the push buttons release cleanly and that the links show no stretch. Omega bracelets are expensive to replace, so a watch sold on a strap alone should be priced accordingly.
• Case finishing. The Seamaster's polished bevels and brushed flanks should meet at crisp lines; a rounded case or a polished-over brushed surface means a heavy refinish. The twisted lugs of the Diver 300M are the first place that shows.
• Movement. Through the display back, the Co-Axial movements show an Arabesque Geneva wave pattern on the rotor and bridges and a free-sprung balance with a silicon spring; the rotor should spin freely and the watch should keep within its tolerance over a few days. A Master Chronometer that runs more than five seconds fast or any seconds slow a day needs attention.
• Service history. Omega recommends service at intervals of several years and services every Seamaster calibre through its own network. A calibre 2500 Diver 300M more than a decade old without a service history should be priced to allow for one; the 8800 and 8900 watches sold since 2018 are only now reaching their first service.
• Box and extras. Diver 300M and Planet Ocean watches come with the Omega box and, on many references, a spare rubber or NATO strap and a changing tool; the 007 Edition comes with both the mesh bracelet and NATO in its own packaging. A full set is worth more than a watch alone.
• Price against the band. An unworn full-set Seamaster offered well below the others deserves a question about the card date, the generation and the kit before anything else.

Our authentication process describes what we inspect before dispatch, and the pre-owned collection shows how we describe condition.

Quick answers

How much is an Omega Seamaster?

Omega's US list prices for the steel Seamaster Diver 300M have sat a little above US$6,000 on the bracelet in recent years, with the Aqua Terra, Planet Ocean and Seamaster 300 in steel listing in the high six to low seven thousands. Bizak's sourced catalogue listed the blue Diver 300M 210.30.42.20.03.001 at US$4,818, the black 210.30.42.20.01.001 at US$5,699, the Aqua Terra 41 blue at US$5,615 and the Seamaster 300 black at US$6,800 on October 26, 2026, all sourced to order.

What is the difference between the Seamaster Diver 300M and the Planet Ocean?

The Diver 300M is a 42 mm watch rated to 300 m with a ceramic wave dial, skeleton hands and a scalloped bezel, on the calibre 8800; the Planet Ocean is rated to 600 m, comes in 39.5 mm and 43.5 mm with broad arrow hands and a thicker case, and adds a 43.5 mm GMT, a 45.5 mm chronograph and the 6,000 m Ultra Deep. The Planet Ocean is the heavier professional tool; the Diver 300M is the lighter everyday diver.

Is the Omega Seamaster a Master Chronometer?

Yes. Every current Seamaster, including the Diver 300M, Aqua Terra, Planet Ocean, Seamaster 300, Ploprof and Railmaster, is Master Chronometer certified by METAS, the Swiss federal metrology institute, for accuracy of zero to plus five seconds a day and resistance to 15,000 gauss. Previous-generation Seamasters on the calibres 2500 and 8500 are COSC chronometers rather than Master Chronometers.

Which Omega Seamaster did James Bond wear?

Pierce Brosnan wore the Seamaster Diver 300M from GoldenEye in 1995, first the blue quartz 2541.80 and then the automatic 2531.80. Daniel Craig wore the Planet Ocean and the Diver 300M from Casino Royale, the Seamaster 300 Spectre edition in 2015 and the titanium Diver 300M 007 Edition 210.90.42.20.01.001 in No Time to Die.

Is the Omega Seamaster better than the Rolex Submariner?

The Submariner is finished to a higher standard, has the Glidelock clasp and a tighter accuracy tolerance, and holds its value because supply is controlled; the Seamaster Diver 300M costs roughly half as much, has a ceramic dial, a display back and 15,000 gauss magnetic resistance, and can usually be bought at list without a waiting list. Which is better depends on whether you are buying a diver to wear or a store of value.

Request an Omega Seamaster sourcing quote

Tell us the family, reference, dial, bracelet or strap, preferred year range, condition and whether the warranty card and the full strap kit are required, plus your budget and timing, through our sourcing enquiry form. We confirm the specific watch, photographs, card and final price before you commit. Catalogue entries: Diver 300M black, Diver 300M blue, 007 Edition titanium, Aqua Terra 41 blue, Aqua Terra 38 black, Planet Ocean 39.5, Planet Ocean 43.5, Seamaster 300, Ploprof 1200M, Railmaster 38; browse the Seamaster collection, the Omega collection, or sell or trade your Seamaster.

Related reading: The best Omega watches · The cheapest Omega watches · Rolex vs Omega: which costs more · Omega Speedmaster Moonwatch guide · Which Omega to buy: Speedmaster, Seamaster or Constellation · Rolex Submariner vs Sea-Dweller · Tudor Black Bay 58 guide · Tudor Pelagos guide · Aqua Terra Day-Date 231.53.42.22.02.001 guide · Omega Seamaster James Bond editions · Omega Seamaster vs Constellation · Seamaster Planet Ocean 600M.