A report from the Environment Agency made the recommendation, saying the region was in a "serious situation".
The period from October 2004 to January 2006 was the driest in some parts of the South East since 1921.
Rainfall has been low across most of England and Wales, but the south of England has been the driest area.
The Environment Agency and the Consumer Council for Water have both said they are more concerned about shortages in the South East than anywhere else in the country.
Four out of the nine water firms in the South East already have some form of hosepipe ban.
Mid Kent Water also has a hosepipe ban in place.
The Environment Agency appealed for similar action to be taken, from early April at the latest, by Thames Water, Folkestone and Dover Water, Portsmouth Water, Essex and Suffolk Water and Three Valleys Water, which supplies customers across north Surrey, north London, Hertfordshire and Essex.
Agency chief executive Barbara Young said both water supplies and the environment were at risk.
"There is still time for rain this winter and spring to reduce the risk of drought, but water companies shouldn't just hope for rain - they must act now in case the weather stays dry," she said.
"If they delay introducing hosepipe bans, extreme steps to manage water supplies over the summer may be needed, such as standpipes and rota cuts."
From October 2005 up to 20 February, south-east England received about 280mm of rainfall, 100mm less than the average for the period.
An Environment Agency spokeswoman said: "We need a lot more to make water resources safe.
"Any rain will help and we're at the right time of the year for rain to have the best possible impact on water resources.
"[But] we're still a long way from the drought being over."
Environment minister Elliot Morley said compulsory water meters were one option for saving water but that there was a stronger case for introducing this in areas of need such as southern England, rather than a national scheme.
Liberal Democrat environment spokesman Norman Baker said compulsory meters would play a vital role in managing resources in the future.