The UK’s online safety regulator, Ofcom, has initiated a formal investigation into Telegram under the Online Safety Act 2023 to assess whether the messaging platform has adhered to its responsibilities to protect UK users from child sexual abuse material (CSAM). This action represents Ofcom’s most prominent enforcement measure against a major messaging platform to date.
This investigation, highlighted by Reuters, signifies a notable step up in Ofcom’s enforcement of the Act against a globally popular messaging service, which has often faced criticism regarding its handling of illegal content.
Following the Online Safety Act’s established enforcement procedure, the investigation requires user-to-user and search services to assess and address risks of illegal content exposure to UK users, including CSAM, and ensure swift removal when detected.
Ofcom has the authority to impose penalties, the greater of £18 million or 10% of applicable global revenue, for non-compliance. In ongoing severe non-compliance, Ofcom can seek court orders for business disruption, potentially leading to internet service providers blocking the platform in the UK.
Opening a formal investigation does not automatically indicate wrongdoing. The Act’s process involves Ofcom collecting and analyzing evidence to determine if a breach has occurred. Should compliance failure be identified, Ofcom issues a provisional decision to the company, allowing it to respond before making any final decision. This process usually takes several months. The same framework is being used in the ongoing investigation into X, initiated in January 2026, following reports of its Grok AI chatbot facilitating the generation and distribution of child sexual images.
Telegram has been developing its relationship with UK regulators. In December 2024, the platform joined the Internet Watch Foundation (IWF), committing to using IWF’s detection tools across public areas, including hash-matching technology for identifying known CSAM, and tools to block AI-generated abuse content.
Ofcom’s March 2026 annual review recognized that Telegram, along with X, Discord, and Reddit, implemented age controls in response to the Online Safety Act. Despite this, the new investigation suggests sufficient grounds exist for a formal inquiry into Telegram’s compliance with CSAM-related duties under the Act.
The core tension in the Telegram case is one that has characterized discussions about the platform for years. Its structure comprises public channels, accessible to detection tools, and encrypted private messages, popular with activists, journalists, and dissidents, but posing inherent limits on content moderation.
The NSPCC commented on Telegram’s IWF partnership in December 2024, noting the improvement in public content handling while emphasizing that “no part of the service should allow perpetrators to act undetected.”
The end-to-end encryption provisions of the Online Safety Act remain contentious, with Signal previously threatening to exit the UK if required to scan private messages. Ofcom has indicated it is not presently inclined to enforce client-side scanning.
The investigation surfaces during a period of intense regulatory scrutiny on messaging and social media platforms across the UK. Since the Online Safety Act’s 2025 implementation, Ofcom has launched investigations into nearly 100 services, issued multiple fines, and, in March 2026, demanded evidence of enhanced child safety measures from major platforms, including Facebook, Instagram, Roblox, Snapchat, TikTok, and YouTube, by 30 April.
The Telegram investigation introduces a significant messaging platform to the enforcement list, previously more focused on pornography sites and niche image boards.
Telegram did not respond to a comment request at the time of the Reuters report. Ofcom promised to update on the investigation as soon as feasible.