How To Date U.S. Postcards by Postage Amount
You can approximate the date a postcard was manufactured by the amount of postage required to mail it. If unused, the stampbox usually has the postage requirements. You can also use this chart if the postcard is used, but with an unreadable postmark date. However, keep in mind that a postcard might be postally used many years after manufacture, or someone may have used a higher denomination stamp than was required.
| Postage Rate | Valid for Years |
|---|---|
| One Cent | 1898 - 1917 |
| 1919 - 1925 | |
| 1928 - 1951 | |
| Two Cents | 1917 - 1919 |
| 1925 - 1928 | |
| 1952 - 1958 | |
| Three Cents | 1958 - 1962 |
| Four Cents | 1963 - 1967 |
| Five Cents | 1968 - May 1971 |
| Six Cents | May 1971 - Mar 1974 |
| Seven Cents | Sep 1975 - Dec 1975 |
| Eight Cents | Mar 1974 - Sep 1975 |
| Nine Cents | 1976 - May 1978 |
| Ten Cents | May 1978 - Mar 1981 |
| Twelve Cents | Mar to Oct 1981 |
| Thirteen Cents | Nov 1981 - Feb 1985 |
| Fourteen Cents | Feb 1985 - Apr 1988 |
| Fifteen Cents | Apr 1988 - Feb 1991 |
| Nineteen Cents | Feb 1991 - 1994 |
| Twenty Cents | 1995 - Jun 2001 |
| Twenty-One Cents | Jul 2001 - Jun 2002 |
| Twenty-Three Cents | Jul 2002 - Dec 2005 |
| Twenty-Four Cents | Jan 2006 - May 2007 |
| Twenty-Six Cents | May 2007 - |
Another clue to postcard manufacture can be found in the address of the publisher. Two-digit postal zones were introduced in 1943, and were in-between the city and state, such as Des Moines 17, Iowa. 5-digit ZIP codes were introduced in Jan 1963, and follow the state, such as Des Moines, Iowa 50304. Zip + 4 codes were introduced in Oct 1983, such as Des Moines, Iowa 50304-0943.