4.7 million accounts gone, the social media age restriction and what it means for audience strategy

The Online Safety Amendment (Social Media Minimum Age) Act 2024 took effect on 10 December 2025. Ten platforms (Facebook, Instagram, Reddit, Snapchat, TikTok, X, Threads, Twitch, Kick, YouTube) must take reasonable steps to prevent users under 16 from holding accounts. On 16 January 2026, eSafety reported that platforms had removed access to about 4.7 million accounts identified as belonging to under-16s in the first half of December.

Self-declaration of age is not sufficient. The eSafety Commissioner’s September 2025 guidance encourages successive validation, sometimes called a waterfall approach. The legal obligation is to take reasonable steps; no single verification method is prescribed for every user.

The audience contraction is real

This is not hypothetical. Millions of accounts have been removed from major platforms in Australia. For brands whose plans relied on registered 13-to-15-year-old audiences, the available account-based audience changes materially. The 4.7 million figure counts accounts, not unique children, and does not measure lost advertising reach. It also does not prove every underage user has been excluded. Brands need to reassess actual reach and their own obligations rather than assume the platform’s action settles both.

Phase 2 Online Safety Codes add further obligations

Nine industry codes covering Class 1C and Class 2 material were registered in 2025, with principal commencement dates of 27 December 2025 and 9 March 2026. Some age-assurance requirements have later commencement dates. These impose obligations on social media platforms, search engines, online games, and app distributors. Mandatory age checks are required for high-risk services, including generative AI services capable of producing explicit or harmful material.

Under the September 2025 announcement, breach of a direction to comply could attract civil penalties of up to AUD 49.5 million.

What this means for channel strategy

The implications are sector-specific, the principle is universal: account availability on major social platforms has changed in Australia. Age assurance also introduces steps into some user journeys. The effect on reach, conversion rates and measurement needs to be tested for each audience.

For marketers in entertainment, education, gaming, and fashion, the channel mix needs reassessment. Platforms that were previously efficient for reaching younger demographics may no longer deliver the same reach or cost efficiency. The discovery surfaces have shifted, and IMO most planning models still have not been updated to reflect that.

The Phase 2 codes place obligations on providers of covered services, including some generative AI services. Using an AI tool to draft marketing copy does not by itself make an organisation a regulated service provider under those codes. If you operate a customer-facing AI service, assess the service’s category, risk and applicable commencement dates. That is a compliance question as well as a brand safety one.