Omega Speedmasters do not have case numbers stamped into them like Rolex serial numbers. Instead they have individual Omega serial numbers stamped into the watch movement. This does mean you need to remove the caseback to be able to see the movement and to find out the Omega movement number. From this, however, you can begin to estimate the date of your Omega.

The only real way of being able to ascertain exactly when an Omega was issued is by contacting Omega directly through their website. They can issue you with an Extract from the Omega Archives for a small charge. This will give you specific information from the archives on how the watch left their production facility and the exact date of your Omega. This extract is simply that – it is not an Omega Certificate of Authenticity.

However for a good estimate of the year of your Omega watch you can date it by checking your movement number against this Omega Movement Number Database.

Omega Movement Number Year
14m 1957
14m 1958
16m 1959
17m 1960
18m 1961
19m 1962
20m 1963
22m 1964
22m 1965
23m 1966
24m 1967
26m 1968
27m 1969
28m 1970
30m 1971
31m 1972
32m 1973
32m 1974
33m 1975
34m 1976
35m 1977
37m 1978
38m 1979
40m 1980
42m 1981
43m 1982
44m 1983
45m 1984
46m 1985
47m 1986