The average household water bill is on course to rise by more than 1-percent.
Scottish Water will increase charges by £6 a year from April 1st.
Bosses say rates continue to be among the lowest in the UK.
Douglas Millican, Chief Executive, said: “Scottish Water continues to provide one of the UK’s best value water and waste water services.
“We have listened to the views of our customers in setting our plans for the next six years. Our customers expect us to build on the significant improvements we have made to water services for the benefit of all our customers in Scotland as we embark on our new, six-year regulatory period.
“Our customers have told us that they value certainty in their charges over the medium term. Today’s announcement signals stability in water charges for the coming years and provides certainty for customers. It follows a major customer consultation exercise and extensive discussion with customers and stakeholders, including the Customer Forum for water, to agree a 2015-21 business plan which is focused on meeting customer priorities.
“Charges allow us to maintain investment – ensuring we continue to provide fresh, clearer drinking water for our customers, while protecting and enhancing the environment and supporting the Scottish economy.
“It means that, by 2021, household bills will have fallen further in real terms – which is good news for customers the length and breadth of Scotland.”