Cookies

Small files (known as ‘cookies’) are put onto your computer to collect information about how you browse the site.

Cookies are used to:

  • measure how you use the website so it can be updated and improved based on your needs
  • remember the notifications you’ve seen so that you’re not shown them again

GOV.UK cookies aren’t used to identify you personally.

You’ll normally see a message on the site before a cookie is stored on your computer.

Find out more about how to manage cookies (opens in new tab).

How cookies are used

Measuring website usage (Google Analytics)

Google Analytics software collects information about how you use the site. This is done to help make sure the site is meeting the needs of its users and to help make improvements.

Google Analytics stores information about:

  • the pages you visit - how long you spend on each page
  • how you got to the site
  • what you click on while you’re visiting the site

We don’t collect or store your personal information (eg your name or address) so this information can’t be used to identify who you are.

Google isn’t allowed to use or share our analytics data.

The following cookies are used:
Name Purpose Expires
_gat This helps us identify how you use GOV.UK so we can make the site better 10 minutes
GDS_successEvents and GDS_analyticsTokens These help us identify how you use GOV.UK so we can make the site better 4 months
_ga This helps us identify how you use GOV.UK so we can make the site better 2 years
ga_nextpage_params This stores data to be sent to Google on the next page you request When you close your browser

You can opt out of Google Analytics cookies (opens in new tab).

Comparing different versions of a webpage (Optimizely)

Optimizely software is used to test different versions of a webpage (or webpages) to see which performs better. This is done to help make improvements and ensure the site is meeting the needs of its users.

The following cookies are used:
Name Purpose Expires
optimizelyEndUserId This helps us identify how you use GOV.UK so we can make the site better 6 months
optimizelyRedirectData This helps us identify how you use GOV.UK so we can make the site better 5 seconds
optimizelyOptOut Tells us that you do not want to take part in user testing on our web pages 10 years

Sessions

A cookie is set to record your session activity.

The following cookies are used:
Name Purpose Expires
mdtp Stores session data When you close your browser
mdtpp Stores session data When you close your browser
mdtpdf Stores session data When you close your browser
mdtprc Stores session data When you close your browser
PLAY_FLASH Stores session data When you close your browser
PLAY_LANG Used to temporarily store your language preference When you close your browser
remme This is used to uniquely identify a user on a device trying to go through the 2SV challenge 7 days
mdtpdi This is used to uniquely identify a device that has interacted with tax services, for internal security auditing 10 years

Our introductory message

You may see a pop-up welcome message when you first visit. A cookie is stored so that your computer knows you’ve seen it and knows not to show it again.

The following cookies are used:
Name Purpose Expires
seen_cookie_message Saves a message to let us know that you have seen our cookie message 1 month

User research banner

You may see a banner about user research when you visit. A cookie is stored so that your computer knows when you have chosen not to see it again.

The following cookies are used:
Name Purpose Expires
mdtpurr Saves a message to let us know that you no longer want to see it again. 1 month

Our satisfaction survey

SurveyMonkey (opens in new tab) is used to collect responses to the survey. If you take part, SurveyMonkey will save extra cookies to your computer to track your progress through it.

The following cookies are used:
Name Purpose Expires
mbox This is used to keep your progress through the survey 30 minutes
SSOE This is used for testing different content and features on the survey website to help make it better When you close your browser
TS5159a2 and TSd0b041 These are used to manage survey traffic by sending your computer to a specific server When you close your browser
ep201 This is used to help us identify how you use the survey 30 minutes
ep202 This works with ep201 to help us identify how you use the survey 1 year

Digital assistant cookies

The HMRC digital assistant and webchat can be found on various HMRC services pages. For the digital assistant and website to work correctly, the following cookies are required:

Name Purpose Expires
inqCA_10006330 Chat activity flag, required for restoring functionality of web chat if (during a chat engagement) the user reloads the page, navigates to a new page within the HMRC site or leaves the HMRC site and returns before the session timeout. When you close your browser
inqVital_10006330 Persistent data about the customer. This cookie stores information about the customer (unique Nuance ID), last chat activity, past purchases, etc. This cookie is used to set the state of sale after the chat and to link chats from the same customer. When you close your browser
tcSrv_10006330 A survey show flag required to show whether the post chat survey used for web chat have been presented to the user. When you close your browser
inqSession_10006330 Session data for current chat. The information stored in this cookie can be used to drive the business rules and to restore chat (e.g. after page reload). Most part of the data is deleted when chat is closed. When you close your browser
inqState_10006330 Information about customer actions for ETL events (Extract, Transform & Load – process of logging data used for reporting). Example: count of chats on site, page markers, count of assisted, etc. When you close your browser
JSESSIONID Cookie used in session tracking. Since HTTP is a stateless protocol, the cookie is created to enable the web chat application to keep the state of the session on the server side. When you close your browser

JavaScript detection

Some pages can provide an enhanced experience when JavaScript is enabled and may use a cookie to detect this.

The following cookies are used:
Name Purpose Expires
JS‑Detection This tells us if you are browsing tax.service.gov.uk while running JavaScript. 1 year
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