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Tariffs from the outside water tariff rises every April are still a postcode lottery. For the largest wholesale areas affecting Castle’s customers April price rises vary from +34% for large customers in the Southern Water area (for clean water services), to reductions of 5-6% in sewerage charges for Thames and Southern.
In summary:
- Thames: water +10.5%, waste -4.9% (includes TE)
- Affinity: water+13.5 to +19.3% (with the higher increase for large customers)
- South East: water +12.8% to +19.8% (with the higher increase for large customers)
- United Utilities: water +18%, waste +9%
- Severn Trent: water -2.25 to +4.6%, waste +8.3%
- Anglian: water+11.7% to 18.6%, waste +9.5% to 12.1%
- Southern: water +30% to 33%, waste -6-6% to +4.1%
Possible Financing and Regulatory Deal For Thames
Thames has announced what looks like a possible financing and regulatory deal, but which lacks key details – for example, it includes a tailored change in ODI incentives, but without enough detail to see how it affects tariffs. It’s probably realistic to assume that this will increase prices rather than reduce them, and is likely to impact tariffs from 2027. The delays in Thames restructuring its finances may end up slowing the increase in tariffs for 2027-30, with a higher increase in 2030.
CMA Publishes Final Decision
Looking ahead, the CMA has now published its final decision on the CMA appeal by 5 companies (Southern, Anglian, Northumbrian, South East, Wessex). This decision reduced the headline impact to an average of 2.2% increment on prices. The highest increase is for South East, at 4%, and the lowest is 0% for Northumbrian. For the other 3 companies, the increases allowed by the CMA are Wessex +3%, Southern +3% and Anglian +2%. These will feature in tariffs from 2027.
PR24 Price Review
The PR24 price review included a whole series of features which provide incentives and penalties, as well as new “gated” allowances. This makes expectations of future charges difficult to estimate – which does not help customers with planning for either operating expenditure or new investment. There may be other changes coming which could increase tariffs, notably reflecting increased energy charges – energy is a major cost necessary for pumping.
Further Changes to Large User Tariffs
There will be further changes to Large User Tariffs running up to 2030, with most water companies phasing in significant price increases over a 3-5 year period, mainly affecting customers who consume over 150Ml annually. This is driven by environmental policy, and appears directly opposed to the approach taken in the energy sector to key customer groups.
This is inevitably a bit of a generalisation – if you have specific queries about your own charges, please contact your Castle Water account manager, or you can email me directly at ceo@castlewater.co.uk
