Substack to require age verification for UK users

Written on 11/26/2025

Substack will now ask UK users to verify their age if they're viewing certain content.substack logo on smart phone

Newsletter platform Substack will require users in the UK to verify their age to comply with the Online Safety Act.

The Online Safety Act, which went into effect late July this year, requires websites containing explicit content to install one of several possible ways to assure a visitor's age, such as one's banking information or a facial recognition scan. It's just one of many age-verification laws that have been enacted globally in the last few years. Adult site Pornhub complies with the UK's law — but some "SFW" sites have started age-verifying as well, such as YouTube.

Now, Substack has become the latest to require more data from its users. On October 20, Substack published a blog post about its position on the Online Safety Act, stating that it "cautions against regulatory measures like these."

"Though they are often well-intentioned, these laws are not necessarily effective at achieving their stated aims, and they come with real costs to free expression," the post states. "They introduce friction, forcing an identification step before people can read on the internet."

The post went on to state that despite this, "we respect the right of countries to set their own laws, and we comply with local regulations where required."

It outlined the steps it would take to comply, including that if content is labeled under a category covered by the law, anyone viewing it on a browser or the Substack app may see a notice requiring them to complete age verification before viewing it. Substack caveated that paid subscribers are verified due to their banking information, and other subscribers may be verified already through other platforms. (This blog also mentions Australia's upcoming age-verification law, but subsequent posts don't.)

The list of content restricted to adults, according to Substack's Help Center, includes:

  • Sexually explicit or pornographic content

  • Content that encourages self-harming behaviors (i.e. eating disorders and suicide)

  • Bullying or harassment

  • Hate targeting people based on protected characteristics (like race and sexual orientation)

  • Violent or graphic material

The platform updated a Help Center page titled, "Why is Substack asking to verify my age?" on Tuesday. Substack explained that a publication's chat, DMs, comments, and Notes may be blurred or blocked if they fit within the Online Safety Act's definition of "potentially harmful content."

It also laid out instructions for how to complete a facial scan. It recommends grabbing a government ID "in case the selfie verification fails," as well.

Substack stated it will retain the age estimate following the verification process.

If content is blurred that you don't believe falls under the Online Safety Act, you can request a manual review.

In the last few years, many users left Substack due to the platform hosting alt-right and Neo-Nazi content. Those posts will now likely get blurred in the UK for non-verified users.