Castle Water is the leading independent water retailer in the UK. We supply hundreds of thousands of businesses, charities, and public bodies throughout England and Scotland.

We provide water retail services to all types and sizes of organisation. We have expertise of working in hard to reach areas, ranging from dispersed rural sites to high density urban environments nationally.

Our customer services are delivered in the UK and we have account management teams to support customers nationwide. We operate extended hours: Monday to Friday, 8am to 6pm, and you can contact us in a variety of ways.

Unlike many water retailers, Castle Water is not associated with any of the UK’s traditional water network owners. We are wholly independent. We only act in the interests of our customers and have an excellent track record of working proactively with water network owners to deliver the right results.

Over the years, our company has grown significantly. In Scotland, we are the Licensed Provider to over 10,000 businesses. We have also pioneered affinity partnerships in the water market with organisations including National Farmers Union of Scotland.

Having established a strong foothold in Scotland, we acquired the business customers of Portsmouth Water and Thames Water in 2016. Castle Water was the first retailer to carry out bulk transfer of English customers and we are highly experienced in switching large and multi-site customers across all industry sectors nationally.

The opening of the water market in England is great news for business. Find out more.

With deregulation, you are no longer restricted to buying from your local water board or water network owner. Instead, we make it easier to get the water you need – at the price you want. We also make life simpler and even more cost effective by offering services such as consolidated billing and direct debit payments.

During our acquisition of the Thames Water business, we also transferred full key account management capability to complement our established expertise in providing water services in the competitive market.

For information about how we work with large water users, customers with sensitive sites, or complex organisations with multi-site premises, please visit our large water users page.

With flexible payment options to suit your cash flow, you can enjoy streamlined services such as one bill for both water and wastewater, or a consolidated bill if you have lots of premises across the country. We also offer a range of additional services to drive efficiency, save money and deliver business success. There are lots of ways we can help make life simpler – and more cost effective!


With Castle Water, expert advice is always on tap! Contact us today to learn more about your options and to see how much money you could save.


    Reduced rates and improved services.

    more info

    Switching is easy. Just follow these easy steps.

    more info

    Learn more about your payment options.

    more info