What does a water Retailer do?
Castle Water is a water retailer. Your retailer is responsible for managing the customer-facing aspects of your water and wastewater services, including:
As a non-household customer, your retailer is always your first point of contact for most queries.
Non-household customers have the right to choose their water retailer, which means you can switch retailers if you wish.
What does a water Wholesaler do?
Water wholesalers (often referred to as water companies) are responsible for the physical infrastructure and supply. This includes:
Your wholesaler is determined by the geographical area your premises is located in and cannot be changed.
For example, the largest wholesaler in England is Thames Water, which covers London and the Thames Valley, whereas Scotland is served by Scottish Water.
How do I find out who my Wholesaler and Retailer are?
If you’re unsure who supplies or retails your water services, Water UK provides an online lookup tool where you can check both:
https://www.water.org.uk/customers/find-your-supplier/
You may have different wholesalers or retailers for water and wastewater, depending on your location.
Who should I contact?
Non-emergency issues
For most issues — including billing queries, account questions, or supply concerns — Castle Water should be your first point of contact.
We’ll liaise directly with your wholesaler on your behalf and arrange the appropriate next steps where needed.
Emergency situations
The only exception is emergency situations that pose a risk to health and safety, such as:
In these cases, you should contact your wholesaler’s emergency phone line directly. You can find the relevant emergency contact numbers here.