Nearly eight million households in the North West, South West and the Midlands could see their water bills reduce by between 5% and 15% by 2025.
Severn Trent Water has proposed to reduce bills by 5% or £18, South West Water by 15% or £73 and United Utilities by 11% or £43 annually.
The draft decisions for 2020 to 2025 also include commitments to spend £1.2 billion in total on improving the environment to reduce pollution, clean 4,500km of rivers and invest in infrastructure projects.
They would also have to reduce leakage by at least 15% by 2025 and provide help for 300,000 customers who are struggling to pay.
Ofwat Senior Director David Black said: “We’ve been very clear that we expect water companies to deliver for customers and the environment and that companies can secure both of these outcomes. Severn Trent, South Water and Utilities all stepped up to the mark with their plans.
“Our draft decisions for these companies show that investment in service and infrastructure can go hand in hand with more affordable bills.”