The point is that apart from Hoverspeed, most of the companies get you there in the same length of time, so you need to look at other ways to compare them such as price or facilities.
The ferry companies are looked at in no particular order. Brittany Ferries, as the name suggests, offers you a choice of routes across to Britanny on the west of France as well as down to Santander in Spain. The boats leave from Portsmouth, Poole and Plymouth in the South and South-West of England in addition to Cork in Ireland.
Condor Ferries, founded in 1964, travel from Weymouth, Portsmouth and Poole towards the channel islands (Jersey and Guernsey) as well as Cherbourg and St Malo in Western France. P&O Portsmouth also leave from the South of England and go towards Le Havre, Cherbourg and Bilbao.
SeaFrance is the only French ferry operator that runs the route from Calais and Dover. It was formed in January 1996 at the end of an agreement between Sealink and SNAT. Typically of a French company, you can expect very good food on SeaFrance ferries.
P&O Stena Line, not to be confused with Stena Line, operate from Dover to both Calais and to Zebrugge in Belgium. Hoverspeed also covers Dover to Calais in addition to Newhaven to Dieppe, and is a much faster way of travelling, with the journey from the Dover to Calais taking less than an hour.
Norfolkline also goes between Dover but goes to Dunkerque, offering passengers a destination with easier access to Holland and Belgium. Norfolkline also offers routes to Waterford and Drogheda in Ireland from Rotterdam in Holland
DFDS Seaways operates from the east of England, leaving from such places as Harwich in Essex and Newcastle up in the north-east. DFDS serve more North Sea destinations - taking in Holland, Sweden, Norway, Denmark and even Germany.
P&O North Sea Ferries cover the same areas. They leave the East and North-East of England going to points in the North Sea. Stena Line also offers a trip from Harwich to the Hook of Holland in addition to going from Holyhead, Fishguard and Stranraer over to Ireland. These are similar routes as those taken by P&O Irish Ferries. P&O Scottish Ferries leave from the very north of Scotland to go to the islands of Orkney and the Shetlands as well as Scandinavian countries.
Another alternative is the Eurotunnel, which takes the Eurostar train, as well as the shuttle carrying cars and other automobiles on the quickest non-air journey over the channel.