Longines Watch Serial Number List
| serial number | year | serial number | year |
| 20,000 | 1870 | 3,815,000 | 1920 |
| 36,000 | 1871 | 3,880,400 | 1921 |
| 52,000 | 1872 | 3,945,600 | 1922 |
| 68,000 | 1873 | 4,047,000 | 1923 |
| 84000 | 1874 | 4,031,000 | 1924 |
| 100,000 | 1875 | 4,148,500 | 1925 |
| 121,400 | 1876 | 4,500,000 | 1926 |
| 142,800 | 1877 | 4,625,000 | 1927 |
| 164,300 | 1878 | 4,750,000 | 1928 |
| 185,700 | 1879 | 4,886,000 | 1929 |
| 207,100 | 1880 | 4,959,000 | 1930 |
| 228,500 | 1881 | 5,031,800 | 1931 |
| 250,000 | 1882 | 5,104,500 | 1932 |
| 291,700 | 1883 | 5,177,000 | 1933 |
| 900,000 | 1884 | 5,250,000 | 1934 |
| 333,300 | 1885 | 5,333,000 | 1935 |
| 375,000 | 1886 | 5,416,000 | 1936 |
| 416,700 | 1887 | 5,500,000 | 1937 |
| 458,350 | 1888 | 5,750,000 | 1938 |
| 500,000 | 1889 | 5,850,000 | 1939 |
| 600,000 | 1890 | 5,950,000 | 1940 |
| 650,000 | 1891 | 6,140,000 | 1941 |
| 700,000 | 1892 | 6,332,000 | 1942 |
| 750,000 | 1893 | 6,523,000 | 1943 |
| 791,100 | 1894 | 6,714,000 | 1944 |
| 832,800 | 1895 | 6,905,000 | 1945 |
| 874,400 | 1896 | 7,107,000 | 1946 |
| 916,000 | 1897 | 7,309,000 | 1947 |
| 957,800 | 1898 | 7,511,000 | 1948 |
| 999,400 | 1899 | 7,713,000 | 1949 |
| 1,124,700 | 1900 | 7,915,000 | 1950 |
| 1,250,000 | 1901 | 8,225,000 | 1951 |
| 1,320,000 | 1902 | 8,535,000 | 1952 |
| 1,440,000 | 1903 | 8,845,000 | 1953 |
| 1,500,000 | 1904 | 9,183,000 | 1954 |
| 1,750,000 | 1905 | 9,521,000 | 1955 |
| 1,850,000 | 1906 | 9,859,000 | 1956 |
| 1,950,000 | 1907 | 10,201,000 | 1957 |
| 2,100,000 | 1908 | 10,544,000 | 1958 |
| 2,250,000 | 1909 | 10,886,000 | 1959 |
| 2,375,000 | 1910 | 11,212,000 | 1960 |
| 2,500,000 | 1911 | 11,538,000 | 1961 |
| 2,750,000 | 1912 | 11,864,000 | 1962 |
| 2,900,000 | 1913 | 12,116,000 | 1963 |
| 3,075,000 | 1914 | 12,368,900 | 1964 |
| 3,250,000 | 1915 | 12,621,000 | 1965 |
| 3,375,000 | 1916 | 12,874,000 | 1966 |
| 3,500,000 | 1917 | 13,839,000 | 1967 |
| 3,625,000 | 1918 | 14,834,000 | 1968 |
| 3,750,000 | 1919 | 15,000,000 | 1969 |
Begining about 1970, it appears that Longines changed their serial numbering system. The numbers below are assumed to be the result of the new numbering.
| serial number | year | serial number | year |
| 50,842 | 1972 | 53,902 | 1980 |
| 52,216 | 1974 | 55,300 | 1982 |
| 53,478 | 1977 |
These are approximate production dates. Accurate annual number lists for Swiss watches are often not available. Some of the dates in this list are interpolated for years for which there may be no accurate list.
Ccwatchmaker has no affiliation with Longines.