Water bills across the Midlands are to go up by 5.7% - nearly three times the rate of inflation - from April.
Severn Trent (ST) said the average bill will rise from £253 annually to £267.
Bills will then average 73p daily and will fund investment of £1m a day in tap water and river quality in the East and West Midlands and Gloucestershire.
ST said the rise is 0.65% below the price limit allowed by regulator Ofwat, and its bills are among the lowest in the country.
Sir James Perowne, chairman of the Consumer Council for Water Midlands, said: "It is regrettable that once again the increases are above the rate of inflation, as some people will struggle to pay the extra cost.
"But I am pleased Severn Trent have not increased charges by the maximum allowed by Ofwat."
ST Investment plans
£400m on maintaining water supplies
£150m improving drinking water quality
£850m maintaining and improving river quality
£350m improving sewers and dealing with sewer flooding
Average household bills for South Staffordshire Water consumers - who get water from that company and pay a sewerage bill to ST - will rise to £238 from April.
ST director of customer relations Jonathan Bailey, said: "Customers tell us their top priority is the safety and reliability of their drinking water supply, and we'll never put that at risk.
"While the pricing regime determined by Ofwat allows us to continue to invest, it also demands even more reductions in our operating costs.
"We'll need to meet new legal standards too, as well as tackling problems such as sewer flooding.
"At 73p a day - about the price of a family's daily milk - we believe water bills still represent good value for money."