Upcoming Water Tariff Changes: April 2026 Update from Castle Water

Castle Water, a supplier on the National Public Sector Water Supply & Services Framework, have provided an update on proposed water tariff changes for 1 April 2026. They have outlined an indicative increase of around 8%, but the picture is highly inconsistent. Increases range widely—from +3% to +30% depending on the customer type and region.

Water and wastewater charges continue to move differently; for example, Southern’s wastewater charges drop by 5.4% while water rises by 18.4%. Some categories, such as Places of Worship under United Utilities, face unusually high increases (up to 22%). These figures are preliminary and may change before final confirmation in January, so budgets should be prepared with caution.