Models
The Omega Seamaster
By the Encore Luxe specialists · Updated October 2026
Few names in watchmaking cover as much ground as the Seamaster. Since 1948 it has been an everyday dress watch, a professional dive instrument, a chronometer, a film icon and an Olympic timer's companion. Today it is a family of distinct watches that share a spirit of robustness. This guide traces its history, explains the main families and offers advice on care.
Key facts
| Introduced | 1948 |
| Significance | Omega's centenary; began as a water-resistant everyday watch |
| Main families | Diver 300M, Aqua Terra, Planet Ocean, Ploprof, Seamaster 300 and vintage Seamasters |
| Movements | Self-winding; modern Co-Axial and Master Chronometer calibres; quartz on some |
| Metals | Steel, titanium, gold, ceramic and combinations |
From everyday watch to dive instrument
Omega introduced the Seamaster in 1948, its hundredth year. The first Seamasters were elegant, water-resistant self-winding watches, inspired by watches Omega had supplied to the British forces. Over the following decades, the name broadened into dive watches. The Seamaster 300 appeared in 1957, the Ploprof in 1970, and the Seamaster Diver 300M in 1993, which later became famous on screen.
The families
Seamaster Diver 300M
The best-known modern Seamaster: a professional dive watch with a unidirectional rotating bezel, a helium escape valve, a screw-down crown and a wave-pattern dial on many versions. Water resistant to 300 metres.
Seamaster Aqua Terra
A versatile everyday watch with Seamaster robustness and a dressier character: a smooth bezel, a dial with horizontal "teak" lines on many versions, and a slim case. Available in a range of sizes, including smaller ladies' models. We currently have an Aqua Terra 150M ladies' 28 mm in steel.
Seamaster Planet Ocean
A larger, more technical diver, water resistant to 600 metres, with a bold bezel and robust case.
Seamaster Ploprof
Short for plongeur professionnel. A professional dive watch first introduced in 1970, with an asymmetric monobloc case, a bezel lock button and exceptional water resistance. Modern versions are rated to 1,200 metres. We currently have an Omega Seamaster Ploprof 1200m in steel, 2011.
Seamaster 300 and vintage Seamasters
The Seamaster 300 continues the 1957 design in modern form. Vintage Seamasters from the 1950s and 1960s, often dress watches with automatic movements, are loved for their elegance.
Movements
Many modern Seamasters use Omega's Co-Axial escapement, designed to reduce friction and extend service intervals. Master Chronometer calibres are certified to stringent standards, including resistance to strong magnetic fields. Some models, especially smaller ladies' Aqua Terras, use quartz movements.
Sizes
Seamasters range from small ladies' models of around 28 mm to robust divers well over 40 mm. Each listing gives exact measurements.
Wearing a Seamaster
The Diver 300M is a sports watch that dresses up easily. The Aqua Terra is a natural everyday watch, as appropriate with a suit as with a jumper. The Ploprof and Planet Ocean are bolder, more technical tools.
Caring for a Seamaster
- Crown and helium valve: screw both down fully before contact with water.
- Water resistance: have it tested periodically, especially on dive watches and after servicing.
- Servicing: Omega generally recommends every five to eight years, depending on model and use.
- Rinse after the sea: in fresh water, especially the bezel.
- Magnetism: Master Chronometer movements are highly resistant to magnetic fields, but older watches can be affected by strong magnets.
- Quartz: batteries should be changed by a specialist to preserve water resistance.
Authentication
Every Omega we offer is examined by our watch specialists. Read how we authenticate an Omega.
Choosing a Seamaster
Begin with how you will wear it. If you swim, dive or simply want a robust everyday sports watch, the Diver 300M is the natural choice. If you want a watch that moves easily between office and weekend, the Aqua Terra is quieter and more versatile. The Ploprof and Planet Ocean are for those who enjoy a bold, technical instrument. Next, consider size: Seamasters range from around 28 mm ladies' models to over 45 mm for the Ploprof, so it is helpful to check the measurements against a watch you already own. Finally, consider era: vintage Seamasters are elegant and characterful but less water resistant, while modern watches are built for the water.
Related: Omega house guide · Rolex Submariner
Encore Luxe is an independent retailer and is not affiliated with Omega.
Questions we’re often asked
- When was the Omega Seamaster introduced?
The Seamaster was introduced in 1948, Omega's centenary year. It began as a robust, water-resistant everyday watch and grew into a family of dive and sports watches.
- What is the difference between the Seamaster Diver 300M and the Aqua Terra?
The Diver 300M is a dedicated dive watch with a rotating bezel and a helium escape valve. The Aqua Terra is a more versatile everyday watch with a smooth bezel and a dressier dial.
- What is the Omega Ploprof?
The Ploprof, short for "plongeur professionnel", is a professional dive watch introduced in 1970, with a distinctive monobloc case and a bezel lock button. Modern versions are water resistant to 1,200 metres.
- How often should a Seamaster be serviced?
Omega generally recommends servicing every five to eight years, depending on the model and how it is worn. Water resistance should be tested more often, particularly on dive watches.