Universal Machine Postmarks
of Great Britain & Northern Ireland
by Paul T Carter
published by the British Postmark Society
A history and detailed checklist of Universal stamp-cancelling machines and their dies (including unified dies, from 1933 onwards, in Hey-Dolphin and Krag single-impression machines).
Includes overall dates of use for all types of machine, providing a timeline for the history of mechanisation at each office.
To open your chosen section, click one of the blue buttons below (scroll down the page to see them all). The geographical sections are data files, which may need magnifying - you can use zoom and download options, both available when you open the file.
Information frequently updated - most recently on 17 July 2025
Listings of Krag & Hey-Dolphin machine postmarks can be found at the following sites:
