Royal Mail Ship

Royal Mail Ship (sometimes Steam-ship or Steamer) is usually seen in its abbreviated form RMS, a designation which dates back to 1840. It is the ship prefix used for seagoing vessels that carry mail under contract to the British Royal Mail. Any vessel designated as "RMS" has the right both to fly the pennant of the Royal Mail when sailing and to include the Royal Mail "crown" insignia with any identifying device and/or design for the ship.

It was used by many shipping lines, but is often associated in particular with the White Star Line, Cunard Line,Royal Mail Lines and Union-Castle Line, which held a number of high-profile mail contracts, and traditionally prefixed the names of many of their ships with the initials "RMS".

While some lines in the past, particularly the Royal Mail Lines, called all their ships "RMS", technically a ship would use the prefix only while contracted to carry mail, and would revert at other times to a standard designation such as "SS".

Originally the Admiralty operated these ships.

The designation "RMS" has been used since 1840. In 1850 contracts were awarded to private companies. Having the title "RMS" was seen as a mark of quality and a competitive advantage, because the mail had to be on time.

The most valuable route, with the highest volume, was between Kingstown (now Dún Laoghaire), in Ireland, and Holyhead in Wales. The City of Dublin Steam Packet Company (CDSPCo) won the contract. They bought RMS St Columa and RMS Llwywllyn from the Admiralty to supplement their Prince Arthur.

In the CDSPCo contract, in 1860, there was a penalty clause of £1 1s 4d for every minute's delay.

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