The designation has been used since 1840. It was used by a large number of companies, but is often associated in particular with the Cunard line and Royal Mail Lines, which held a number of high-profile mail contract business, and which traditionally prefixed the titles of all its ships with the initials "RMS". The best-known ship carrying the prefix is almost certainly the RMS Titanic of the White Star Line.

Technically, a ship would use the prefix only while contracted to carry mail, and would revert at other times to a standard type designation such as "SS".

Previously, the Admiralty operated these ships . In 1850 contracts were awarded to private companies. 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 and purchased RMS Saint Columa and RMS Llwywllyn from the Admiralty.

Having the title "RMS" was seen as a mark of quality and a competitive advantage, because the mail had to be on time. In the 1860 CDSPCo contract there was a penalty clause of £1 1s 4d for every minute's delay.

In recent years the shift to air transport for mail has left only two ships with the right to the prefix; RMS St. Helena, which serves the island of St. Helena in the South Atlantic, and RMS Queen Mary 2. QM2 was conferred "RMS" by Royal Mail when she entered service in 2004 on the Southampton to New York route as a gesture to Cunard's history.

The Royal Mail continues a form of this tradition on modern day airliners. The UK's flag carrier airline, British Airways is contracted to carry mail on some of its scheduled long-distance routes. Aircraft operating these routes with the facilities to carry mail are allowed to display the Royal Mail's logo and crest on their fuselage, usually alongside their registration markings.

The less common designations RMMV, for Royal Mail Motor Vessel, and RMMS, for Royal Mail Motor Ship, were used for a period when RMS was restricted to steam-ships. Motor Ship indicates that propulsion is provided by diesel rather than steam. The designation TS as in TSMV before the name of the vessel would indicate that it was driven by twin screws.

List of RMS Ships

See also

• Union-Castle Line

External links

• Historic Ocean Liners
• RMS Caronia "Green Goddess" Time-Line
• Titanic Archive

Notes