New legislation came into effect on 26 May 2011 that changed the rules on cookie use by websites.

This means that websites must clearly state how they use cookies and ask each new visitor for permission to use cookies.

What are cookies?

Cookies are small text files that are placed on your computer by websites that you visit. They are widely used in order to make websites work, or work more efficiently, as well as to provide information to the owners of the website.

Most web browsers allow some control of cookies through browser settings. More information about cookies, including how to block and/or delete them, via a range of common browsers, can be found at

How we use cookies

We use cookies to identify registered customers by their username.

You can block cookies by activating the setting on your browser which allows you to refuse the setting of all or some cookies. However, if you select this setting you may be unable to access certain parts of our site.

We also use Google Analytics to collect information about how visitors use our site. The Google Analytics cookies help us to improve our site. The cookies collect the information in anonymous form.

This information will provide us with general information about the users of our website, providing us a better understanding of user requirements. We will not attempt to attribute such traffic information to anything that is personally identifiable.

Additionally, information relating to the Internet Protocol (IP) address, browser and operating system may be observed.

The cookies we use

The table below explains the cookies we use and why.

Cookie Name Purpose More
Session ID ASP.NET_SessionId This is a unique ID that is associated to you whilst you use our website. Once you close the browser or log out of the website then this cookie will be deleted.
Authentication ASPXAUTH This cookie is used to identify you once you log in to our website. Once you close the browser or log out of the website then this cookie will be deleted.
Google Analytics _utma
These cookies are used to collect information about how visitors use our website. We use the information to compile reports and to help us improve the website and helps us to ensure content is tailored to meet what users want and need. The cookies collect information in an anonymous form, including the number of visitors to the website, where visitors have come to the website from and the pages they visited. Click here for an overview of privacy at Google
Thames Water sIFRFetch This cookie enables us to change the fonts on our website to match our corporate font found on all our literature.
Thames Water TWAC This cookie is used to remember that you have accepted our cookie policy and prevents the policy pop-up from appearing in future visits. Please note that if you delete cookies this will reappear.

What happens if I don't want to accept your cookies?

If you don't wish to accept our cookies you will not be able to use some parts of our website including logging in and ordering searches.

It also means the cookie policy will continue to be visible as it takes a cookie to remember that you don’t want to accept cookies.

How do I delete cookies?

Thames Water will not use cookies to collect personally identifiable information about you. However, if you wish to restrict or block the cookies which are set by Thames Water websites, or indeed any other website, you can do this through your browser settings. The 'Help' function within your browser should tell you how.

You can also clear our cookies using the button below.

Clear cookies

Alternatively, you may wish to visit which contains comprehensive information on how to do this on a wide variety of browsers. You will also find details on how to delete cookies from your computer as well as more general information about cookies. For information on how to do this on the browser of your mobile phone you will need to refer to your handset manual.