What is the __zlcstore cookie?
__zlcstore is created by Zendesk scripts (Zendesk Chat, formerly known as Zopim, now part of the Zendesk Widget/Messaging suite) when a website embeds the Zendesk chat or support widget. It is not an HTTP cookie sent by a server, but an entry written directly to the browser's localStorage by Zendesk's JavaScript code.
It typically appears as soon as the Zendesk script loads and initializes the chat widget on the page, whether or not the visitor actually interacts with it.
What data it stores
It stores internal data used by the widget to maintain its state and display preferences across sessions (for example identifiers or settings tied to the Zendesk account instance associated with the site). Zendesk does not publicly document the exact value format, and it may vary between widget versions.
Being a localStorage entry, the data stays stored locally in the browser and is not automatically sent with every HTTP request the way a classic cookie is; it is read by the Zendesk script when the widget loads and, where relevant, transmitted to Zendesk's servers through the widget's own API calls.
What it is used for
Its purpose is purely functional: it lets the Zendesk widget recognize the visitor's preferences and state related to the chat/support tool (for example the widget configuration tied to the site), so the chat experience stays consistent across repeat visits.
For the site owner, this storage supports the proper functioning of the chat-based support channel offered to visitors, and plays no role in statistics or advertising.
Does it require consent?
CookieFix classifies __zlcstore under preferences (functional). Although it stores technical data needed for the widget to work, because it belongs to a third-party service (Zendesk) and is not strictly necessary to deliver content explicitly requested by the user, it is treated under ePrivacy (implemented in Romania via Law 506/2004) as requiring prior visitor consent, similar to a preferences cookie.
- Site owners should list it in their cookie policy, naming the provider (Zendesk) and purpose (chat/support widget functionality).
- The Zendesk script that sets this entry should only load after consent for the preferences/functional category is obtained, not by default on page load.
How to block or delete __zlcstore
Visitors can remove the entry through their browser's site-data settings (localStorage/site data management, separate from classic cookies), or by using private/incognito browsing.
At the site level, the owner should ensure the Zendesk script is not loaded until the visitor consents to the preferences/functional category. A CMP such as CookieFix can handle this automatically, blocking execution of the Zendesk widget until consent is given, preventing premature storage of data like __zlcstore.
Frequently asked questions
It is a localStorage entry, not a classic HTTP cookie, but under ePrivacy and GDPR it is treated the same way as a cookie because it involves storing data on the user's device.
It is set by Zendesk scripts (the Zendesk chat/support widget, formerly also known as Zopim) when embedded on a website.
Yes, since it is classified as preferences/functional and tied to a third-party service, it requires prior visitor consent under Law 506/2004 and GDPR.
It can be cleared from the browser's privacy settings under stored site data (localStorage), or it simply won't appear if the Zendesk widget is never loaded.