Your Water Bill Is Going Up — Here's Why

Ofwat, the government regulator that sets rules for water companies in England and Wales, has approved an extra £3.4 billion in spending by those companies. This comes on top of a £104 billion spending plan agreed in late 2024. The decision means household water bills will go up before the end of the decade. Thirteen water companies had asked for £4.3 billion in extra money, saying they had run into costs they didn't anticipate (The Guardian).

The regulator approved about 79% of what companies wanted. The extra money adds to the spending plan for the period from April 2025 to March 2030, bringing the total to just under the £108 billion the industry originally asked for five years of work. In other words, even though Ofwat initially set the budget at £104 billion, the final number now lands only a few billion pounds short of what companies wanted from the start.

The extra spending is split across several areas. £1.2 billion will go toward protecting water services and equipment. Another £477 million is set aside to connect new housing and datacentres to water and sewer systems. A further £34 million is aimed at reducing toxic chemicals in the water to improve drinking quality (The Guardian).

Five companies — Southern Water, Thames Water, Severn Trent, Wessex Water, and South East Water — were given permission to raise bills above what they had originally planned before the end of the decade. Southern Water alone is set to collect £5.8 billion through customer bills from 2024-25 to 2029-30, which works out to an average increase of £183 per household (Ofwat respondent document).

A look at each company shows how Ofwat made its decisions. United Utilities was allowed £995 million of the £1.11 billion it asked for. Severn Trent received £329 million out of £481 million sought. South West Water was granted £180 million. Across the board, the regulator approved most of what companies wanted but trimmed each request rather than giving the full amount (The Guardian).

Helen Campbell, Ofwat's executive director for delivery, said the funding "would allow water companies to deliver without delay" and would help "unlock housing development and boost business growth." The £477 million aimed at housebuilding and datacentre connections reflects how water infrastructure has become a roadblock for economic growth, especially in areas where new housing and large datacentres are planned.

The broader context here is that the water sector in England and Wales needs far more money than it used to. The £104 billion plan approved in late 2024 was already a big increase from earlier years, driven by decades of underinvestment, stricter environmental rules, and the mounting cost of fixing sewage discharges and pipe leaks. The fact that Ofwat added £3.4 billion on top through a supplementary process rather than waiting for the next regular review suggests the 2024 plan underestimated how much money the sector needs in the near term. Companies asked for £4.3 billion in extras and got most of it, which points to a significant gap between the original budget and real costs.

For households, the result is simple. Bills were already going to rise under the 2024 plan. This extra spending pushes them up further. The five named companies can now charge more than originally planned. The exact amount of the additional increases for customers of Thames Water, Severn Trent, Wessex Water, and South East Water is not spelled out in the current decision, but the direction is clear: consumers will pay a larger share of the sector's costs than the original plan implied.

What is uncertain is whether even the new total of £107.4 billion will be enough. Companies asked for £4.3 billion and received £3.4 billion, leaving about £900 million in identified needs without funding. If costs keep rising faster than Ofwat's budgets allow, the sector may come back for more money before the next major review in 2030. The supplementary process used here shows that such mid-period adjustments are now a normal part of how water regulation works, not a one-off event.