The service originated in 1891 when the FR Co. was party to an agreement on the carriage of Railway Letters made between the G.P.O.
The agreement specifies firstly the conditions under which the service is permitted to operate and secondly the provision of a label (supplied by each participating railway company) to be affixed to the face of the letter.
[3] FR Railway Letter Fee labels (stamps), for the reinstatement of the service, were designed by volunteer Michael Seymour, the FR Co. Archivist (as were all subsequent stamps and pictorial cancellations until his death in February 1999).
The stamps, and many later issues, were printed by T. Stephenson & Sons Ltd. Festiniog Railway Letters were initially accepted at the following stations when staffed – Porthmadog, Dduallt, and Tan-y-bwlch, and also on the trains.
The G.P.O./Royal Mail insisted that the normal postage be paid with Post Office stamps in addition to any railway letter fee and this condition continues.
As time went on most companies, including BR, resorted to the use of parcel labels, often with hand written values, or latterly rubber stamps.
Until 1974, BR set the Railway Letter Fee (a complex fare structure) and this was often changed without warning or notice.
Under the agreement, BR also benefited since it was no longer required to accept letters from a minor railway without the payment of an additional fee.
[5] Changing commercial circumstances caused BR to withdraw completely from this nationwide service on 8 June 1984.
Examples of early Victorian railway letter fee stamps, and later, are to be seen in the National Philatelic Collection in London.
A reply was later received, stating that The Queen has been graciously pleased to accept the stamps for inclusion in the Royal Philatelic Collection.