He was a member of the Religious Society of Friends and originally worked at the Gillow cabinet making business in Lancaster.
While working as a station master at Milton (later Brampton) on the Newcastle and Carlisle Railway, he devised the idea of a new type of railway ticket: a small piece of cardboard, pre-printed with journey details (as opposed to the then current hand-written paper bill).
The invention which made Edmondson's fortune was his final development: a machine which would print tickets in batches complete with the serial numbers.
The South Tynedale Railway, based at Alston, Cumbria, operates an 0-4-0 Henschel-designed steam locomotive, which was named after Thomas Edmondson on the 125th anniversary of his card ticket invention.
The Norwegian State Railways (Norges Statsbaner - NSB) used Edmondson Card Ticket until the late 1990’s, some small stations in the Oslo local traffic area being the last to sell them.