The abbreviation ‘EKD’ is frequently used in auction catalogues, exhibits and reference books, and means ‘Earliest Known Date. In philately, and in particular Postal History, it relates to a particular stamp, cover, postmark or other associated aspect of the delivery being the earliest date recorded, whether that be an issue, country, region or service.

This is a very important aspect of collecting and is fundamental to the study of any topic. To collectors, and especially those who exhibit competitively, EKD material is coveted and as such it generally carries a premium when sold. By their very nature, EKD material is rare, but a word of warning. From time to time, an EKD can be superseded when an earlier example is discovered in a previously unknown source.


The above cover is an example of an ‘EKD’ which comes from the Steven C. Walske collection; USA: San Francisco as a Postal Hub from 1849 to 1869, and is an 1869 USA issue of Pairs of the 10¢ and 30¢ that are the earliest known use from Japan.