Water and sewerage bills are to rise by around £20 from April, regulator Ofwat has said.
The average bill will increase by 0.5% above inflation to £376, taking into account a rate of inflation of 5.2%, the water companies' watchdog said.
The announcement comes after Ofwat pulled back from deep cuts in household bills in 2009 in its final decision on prices for the next five years.
But the regulator has insisted that its challenge of companies' proposed bill rises means that across England and Wales average bills are set to remain broadly in line with inflation by 2015 - around 10% below what companies had asked for before inflation has been factored in.
Ofwat chief executive officer Regina Finn said: "When we set limits on prices, we listened to customers. They told us they wanted bills kept down, while maintaining safe, reliable water supplies.
"We challenged companies hard to deliver this.
"Our decision meant that, before inflation, average bills would remain broadly stable between 2010-15.
"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."
She added: "Companies are investing £22bn by 2015 - more than £935 for every property in England and Wales.
"This will deliver benefits to us all - from continuing to improve reliability of supplies to cleaner rivers and beaches.
"If companies don't deliver on their investment promises, we will take action."
The bill changes for this year will come into effect from April and apply until the end of March next year.
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.
The regulator said investment between 2010 and 2015 would allow companies to ensure that customers continue to see improvements and receive a reliable supply of drinking water.
The average figure shows variations in bills for water and sewerage companies.
A table released by Ofwat shows an increase of 8.2% at Southern Water, or £31, compared with 3.8%, or a £16 rise, at Dwr Cymru Welsh Water.