Who the Act applies to:

The Act’s duties apply to search services and services that allow users to post content online or to interact with each other. This includes a range of websites, apps and other services, including social media services, consumer file cloud storage and sharing sites, video-sharing platforms, online forums, dating services, and online instant messaging services.

The Act applies to services even if the companies providing them are outside the UK should they have links to the UK. This includes if the service has a significant number of UK users, if the UK is a target market, or it is capable of being accessed by UK users and there is a material risk of significant harm to such users.