Customers of Welsh Water are set to have the smallest rise in their bills in England and Wales, according industry regulator Ofwat.
Their combined water and sewerage bills are expected to rise by £11 or 2.7%.
Average bills in England and Wales will go up by 4.6% this April to £356. For Severn Trent customers in Wales, the average increase will be £13 or 4.3%.
Dee Valley customers, whose bill only includes water charges, can expect bills to rise over 5% at £7.
The Consumer Council for Wales, which represents the interests of water consumers in Wales, has urged single person households to consider switching to a metered water supply.
Chair Diane McCrea said: "If you are single person, or two people who don't use a lot of water, check whether you are on a meter and whether you could save money with your water bill by being on a meter.
"Because of the way the regulations are set, metered customers don't pay quite as much, on average, as those who are on [the] rateable value [of their property].
"We know that, still, about 70% of people in Wales don't have a meter. That's something the single person households can think about to reduce their water bill.
Ofwat said the profits generated by higher prices to water customers would help finance £22bn of spending on improved services.