When business owners get in touch with Castle Water, they often find that the biggest stumbling block in switching supplier is the simple fact that they do not know who their current supplier is. In reality, unless you actively keep an eye on your water activity and bills, it is not easy to know who your supplier is, or even why they are your supplier.

In this blog post, we’ll be looking at how to find out who your business water supplier is, how the supply chain is traditionally set-up, and how you have the right to switch supplier as you see fit.

Finding your domestic supplier

Castle Water provides business water services; however, you may have come across this page while looking for your domestic supplier.

Castle Water is always here to help, so here is how anyone in the UK can find out who their domestic water supplier is:

  1. Go to this page on the Water.org.uk website
  2. Enter your postcode
  3. You will be told the provider of your water and sewerage with a link to their site

If you live in Scotland, domestic water is provided by Scottish Water.

If you live in Northern Ireland, domestic water is provided by NI Water.

Remember this is only applicable for finding your domestic suppliers, so if you’re looking out for your business water supplier, read on.

Finding your business water supplier

Since the UK water market changed in 2017, most businesses in the UK have a dedicated water retailer, like Castle Water, looking after their billing. The simplest way to see who your business water supplier is will be to find and check a recent water bill.

Can’t find a bill? Luckily, there is official government information available on the Open Water website here which lists the different companies which could be your supplier be default, based on region.

I think Castle Water is my supplier, but I’m not sure?

If you’ve recently got a water bill in the post from Castle Water, and don’t know why, please read this post on how Castle Water may be your water retailer. If you didn’t choose to switch to Castle Water, your business may have been transferred to us as part of an acquisition by your wholesaler.

Are you stuck with your supplier based on where you are located?

No. If your business water supplier tells you as such, it’s likely not true. The changes made in the UK water market were done for the benefit of the consumer, so they would have the freedom to go with whoever they wanted. Find out more information on how to switch water supplier here.

If you’re having trouble switching, our award-winning customer service team will be able to help.

Are water wholesalers and retailers/suppliers the same thing?

No. The change in the market has created a distinction you should always keep in mind.

Water wholesalers are the companies which are responsible for looking after the local network. For example, while Thames Water has to care for the water supply in most of Greater London. Whereas Castle Water, are the retailer/supplier who looks after billings for customers in the area.

More information on the distinction between wholesalers and retailers can be found here.

Can I switch water supplier?

Yes. The market is open to give businesses the opportunity to choose who their retailer is. As the top-rated water retailer in the UK, according to Trustpilot users, Castle Water can help you switch and save in no time at all.

To find out how, click here.

Why would someone want to change water supplier in the UK?

You may find yourself asking the question: why should I switch business water supplier? Similar to any starting any service contract, it is important to shop around and see which deal is the best for your business. When initially thinking of switching supplier, ask yourself:

  • Do I want bills to come down?
  • Do I want improved services?
  • Do I want wastewater in a better condition?

If you said Yes to any of the above, get in touch with the Castle Water team today.

So what am I responsible for?

There are a few things every business has to take responsibility for on an internal level when looking at their water supply, including the likes of drinking water and washing facilities. Your company is also responsible for paying for any water you use and for the drainage of liquid waste from your premises.

We recommend reading this blog post to find out more on personal water responsibilities.

Can Castle Water help with changing business water supplier?

Castle Water is the UK’s leading independent business water supplier, having helped thousands of UK businesses, charities and public bodies change water supplier.

We've got more 5-star Trustpilot reviews than all other water suppliers combined and offer award-winning water and wastewater services.

The easiest way to switch is by getting in touch directly with the customer service team. You can call them directly on 01250 718 700 (lines are open from 8 am to 6 pm, Monday to Friday).

Alternatively, you can chat to us online or email by contacting us here.


We're helping businesses in England & Scotland save on water bills, and with more 5-star Trustpilot reviews than all other water retailers combined - our customers recommend us.

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