Cookies can be used to store users preferences and other information about visits and actions. Cookies come in two flavours, first-party and third-party. First-party cookies are set by the site or application you are visiting and can only be read by them. Third-party cookies are set by a different web site or application than the one you are currently visiting. They are generally used to track users between different web sites and applications and to display more relevant advertising. Additional cookie information is available from our main cookies page.
The following tables explain the cookies used, what they are for and when they expire:
First-party cookies
| Name | Domain | Expires | Category | Source | Purpose |
|---|---|---|---|---|---|
| _clsk | .ordnancesurvey.co.uk | 24 hours | Targeting/Marketing | Microsoft | Used by Clarity for synchronisation, tracking users, advertising and analytics. |
| _ga | .ordnancesurvey.co.uk | 1 year | Performance | Used by Google Analytics to identify and track users. | |
| _clck | .ordnancesurvey.co.uk | 1 year | Targeting/Marketing | Microsoft | Used by Clarity for synchronisation, tracking users, advertising and analytics. |
| _ga_59ZBN7DVBG | .ordnancesurvey.co.uk | 1 year | Performance | Used by Google Analytics to identify and track users. | |
| CookieControl | .ordnancesurvey.co.uk | 8 months | Strictly necessary | CIVIC | Used by Cookie Control to store cookie preferences. |
| TS016beea5 | .ordnancesurvey.co.uk | Session | Strictly necessary | F5 Networks | Used by BIG-IP ASM domain validation for security management. |
| TS016beea5028 | .ordnancesurvey.co.uk | Session | Strictly necessary | F5 Networks | Used by BIG-IP ASM domain validation for security management. |
| _ga_E5T3PCFCG7 | .ordnancesurvey.co.uk | 1 year | Performance | Used by Google Analytics to identify and track users. | |
| vngage.id | .ordnancesurvey.co.uk | Session | Functionality | Puzzel | Used by Vergic chatbot to record and measure user interaction during chat sessions. |
| vngage.lkvt | .ordnancesurvey.co.uk | 8 months | Functionality | Puzzel | Used by Vergic chatbot to record and measure user interaction during chat sessions. |
| vngage.vid | .ordnancesurvey.co.uk | Session | Functionality | Puzzel | Used by Vergic chatbot to record and measure user interaction during chat sessions. |
| psCurrentState | .ordnancesurvey.co.uk | Session | Functional | Puzzel | Used by Web Chat & Chatbot to contain the state of current chat session. |
Last audited on: 03 June 2025