The average water bill in England and Wales will rise by 5.7% from April this year, the water regulator Ofwat has announced.
The increase - which is 0.5% above inflation - will add £20 to the average 2012/13 bill, taking it to £376.
Ofwat defended the rise, saying it was necessary for a multi-billion pound investment programme and was roughly in line with inflation.
It was also far less than the 10% that water companies had asked for.
The watchdog's CEO Regina Finn said: "We understand that any bill rise is unwelcome, particularly in tough economic times. Inflation feeds through into water bills, and this is driving these rises.
"We will make sure customers get value for money."
The impact of the new charges will vary for households depending on the company that supplies them and whether or not they have a water meter, Ofwat said.