I am indebted to Peter Stubbs for much of the information below (extracted from Peter's site www.edinphoto.org.uk) and his permission for allowing me to use this on the Harberton website.
Summary
United Kingdom postcards can be roughly dated from their FORMAT. Many old postcards were never posted. If they were, the posting date may be shown on the FRANK. If this is unreadable, the STAMP (if any) indicates the approximate year. Below are rules-of-thumb on dating PCs. Most of this info was gleaned from two excellent web pages, which are on: PC stamps http://www.edinphoto.org.uk/0_PC_0/0_post_card_history_-_stamps_postage_rates_uk_1890s-1952.htm and PC history http://www.edinphoto.org.uk/0_PC_0/0_post_card_history.htm.
FORMAT
1870 First (plain) PC
1894 First (picture) PC
1895 Court Card 4¾" x 3½"
1899 Standard size, message on front
1902 Divided backs, message on back
1926 Maximum & minimum sizes fixed
STAMPS
1890-1900 Victoria, ½d, vermillion
1900-1901 Victoria, ½d, blue-green
1902-1904 Edward VII, ½d, blue-green
1904-1910 Edward VII, ½d, yellow-green
1911-1912 George V, ½d, green (¾ head)
1912-1918 George V, ½d, green
1918-1921 George V, 1d, red
1921-1922 George V, 1½d, red
1922-1934 George V, 1d, red
1934-1936 George V, 1d, red
I am indebted to Peter Stubbs for the above information (extracted from Peter's site www.edinphoto.org.uk) and his permission for allowing me to use this on the Harberton website.
Victoria to 1901
Edward VII - 1901 to 1910
George V - 1910 to 1936
Edward VIII - 1936
George VI - 1936 to 1952
Elizabeth II - 1952
Numbers up to No. 18520 were taken prior to 1886
From then, thestarting number for each year is as follows:—
| 18521 – 1886 | 51142 – 1904 | 71721 – 1922 |
| 19500 – 1887 | 53180 – 1905 | 73333 – 1923 |
| 20475 – 1888 | 55341? – 1906 | 75416 – 1924 |
| 21450 – 1889 | 57201 – 1907 | 76667 – 1925 |
| 22421 – 1890 | 59460 – 1908 | 79014 – 1926 |
| 28140 – 1891 | 61298 – 1909 | 79313 – 1927 |
| 29865 – 1892 | 62187 – 1910 | 80652 – 1928 |
| 31590 – 1893 | 63077 – 1911 | 81599 – 1929 |
| 33315 – 1894 | 64058 – 1912 | 82990 – 1930 |
| 35040 – 1895 | 65149 – 1913 | 83725 – 1931 |
| 37121 – 1896 | 66516 – 1914 | 84911 – 1932 |
| 38962 – 1897 | 67714 – 1915 | 85424 – 1933 |
| 40804 – 1898 | 67868 – 1916 | 86015 – 1934 |
| 42852 – 1899 | 67894 – 1917 | 86471 – 1935 |
| 44900 – 1900 | 68020 – 1918 | 87164 – 1936 |
| 46320 – 1901 | 68796 – 1919 | 87845 – 1937 |
| 48082 – 1902 | 69357 – 1920 | 88252 – 1938 |
| 49125 – 1903 | 69918 – 1921 | 88855 – 1939 |
| 88958 – 1940 |
Source: Roger Blake, Beacon Hill