Online platforms will ping Australian teenagers through over a million accounts in coming days offering a choice: download data, freeze profiles or lose the lot when a world-first ban on kids using social media went into effect on Monday.

TikTok, Snapchat and Meta's Facebook, Instagram and Threads are poised to deactivate accounts registered by users under 16, five people with knowledge of the plans said.

Australia's remaining 20 million social media users – four-fifths of the population – can expect little interruption, the people said, as platforms promise low-fuss compliance with a law which puts Australia ahead in the protection of youths online.

The picture is a departure from the chaotic scenarios painted during a year of protest by platform operators fearing a loss of users as well as a $32 million fine for noncompliance. Firms had argued mandatory age checks would subject users to endless log-ins, be invasive or inaccurate and be easy to circumvent.

In practice, social media firms will lean on software they already employ to guess age based on engagement through "likes," for instance, rather than the frequent input and verification of birth dates, the people said.

With that software long-established, having originally been developed for marketing, firms will generally resort to so-called age assurance apps only when users complain of being incorrectly blocked, said the people, declining to be identified as the plans are not yet finalized.

Still, the approach is open to teething problems. Anyone can contest bans through age assurance apps which are being deployed at scale for the first time and which trials showed worked but sometimes with unacceptable error rates – typically along the lines of blocking 16-17 year-olds or approving 15 year-olds, with latter cases potentially exposing companies to fines.

(Cover via VCG)