Omega 503

Last updated: July 26, 2025

Brand

Caliber Number

503

Production Period

1955-1959

Lignes

12.5′′′

Diameter

27.9 mm

Height

6.55 mm

Power Reserve

Unconfirmed

Frequency

19,800 A/h (2.75 Hz)

Jewels

20

Escapement

Swiss Lever

Anti-Shock Device

Incabloc

Hand Count

4

Manufacture Region

Unconfirmed

Functions

Hours, Minutes, Central Seconds, Date, 24-Hour Indicator

Omega 503 Description

The Omega Caliber 503 is a historically important movement from the mid-1950s, as it was part of Omega’s first series of full-rotor automatic movements (the 50x family) that replaced the earlier “bumper” automatics. Introduced in 1955, this chronometer-grade caliber was technologically advanced for its time, featuring not only a date complication in a window but also a distinct 24-hour indicator sub-dial, which served as a day/night display. This combination of features was reserved for high-end models like the Globemaster, Seamaster Calendar, and early Constellations. The Caliber 503 represents a key transitional moment for Omega, combining the newfound efficiency of a 360-degree rotor with useful complications, paving the way for the legendary 55x/56x series that would follow.

Watches Using The Omega 503 Caliber

A vintage Omega Seamaster 2849 Calendar wristwatch with a black dial, silver hour markers, date window at 3 o’clock, silver case, and brown leather strap against a plain background.
A gold Omega wristwatch with a silver dial and date display, featuring a gold metal band.
A vintage Omega Costellation 2852 wristwatch with a round beige dial, gold hour markers, and a green leather strap, viewed from the front. The dial displays the Omega logo and “Automatic Chronometer Officially Certified.”.
A vintage Omega Seamaster 2922 wristwatch with a round silver dial, black leather strap, two crowns, and a date window displaying “28.” The hour and minute hands point to about 2:13. The watch is photographed on a light background.
A silver Omega Seamaster Calendar 2849 wristwatch with a tan leather strap, cream dial, silver hour markers, and a date window at the 3 o’clock position, displayed on a white background.
A vintage Omega Seamaster 14765 wristwatch with a cream-colored dial, silver hour markers and hands, brown leather strap, and the words Omega Automatic and Seamaster on the face.
A vintage Omega Seamaster 300 165.024 wristwatch with a black dial, bold luminous hour markers, black rotating bezel, and a black fabric strap, displayed on a plain light background.
A gold and silver Omega Seamaster 14363 automatic wristwatch with a cream dial, gold hour markers, and a two-tone metal link band, shown against a plain white background.
A stainless steel Omega Constellation wristwatch with a silver dial, black hour markers, date window at 3 o’clock, and a metal link bracelet. The face reads Omega Automatic Chronometer Officially Certified.
A vintage Omega Seamaster 2846 wristwatch with a cream dial, silver case, and brown leather strap. The face displays Arabic numerals at 12, 3, 6, and 9, along with the iconic Omega logo and Seamaster label.
A blue Omega Dynamic 135.033 Genève automatic wristwatch with a round stainless steel case, blue dial, silver hour markers, a date window at 3 o’clock, and a blue perforated leather strap.
A vintage Omega Seamaster Cosmic wristwatch with a black dial, silver indices and hands, a stainless steel case, and a tan leather strap. The words Omega Automatic and Seamaster Cosmic are visible on the dial.
A stainless steel Omega Seamaster 166.010 wristwatch with a silver dial, black hour markers, date window at 3 o’clock, and a metal link bracelet, photographed from the front against a plain background.
A silver Omega Constellation 167.005 wristwatch with a beige leather strap, white dial, black hour markers, and silver hands. The watch face displays Omega Automatic Chronometer Officially Certified.
A gold Omega Constellation 14381 automatic chronometer wristwatch featuring a white dial, gold hour markers, and a brown leather strap. The watch face proudly displays the Omega logo and Constellation text.