How to use CometChat across multiple sub-domains?

CometChat v3.0.9 and higher versions, provides full cross-domain support. You can run CometChat across multiple domains/sub-domains using this feature.

An ideal use of this feature is when you have CometChat installed at and also want to use it on

To use CometChat across multiple sub-domains, follow the steps listed below:

    1. Edit cometchat/config.php and set BASE_URL to the full path e.g.

    1. Then set CROSS_DOMAIN to 1

  • Crossdomain

    1. Add the following code to the site template of your sub-domains (remember to include the full URL path).

  • Add the code immediately after tag:

    <link type="text/css" rel="stylesheet" media="all" href="" /> 
    <script type="text/javascript" src="" charset="utf-8"></script>

    Your users must be logged into your main site inorder to use CometChat in your sub-domains.

    Use of CometService or alternatives is strongly recommended when using CometChat in cross-domain environment.

    Not finding what you need?

    The CometChat team is here to help!