The figure has been revealed in a Tusla report to the Dáil Public Accounts Committee.
Almost 300 child asylum seekers were found to be adults over the past four years.
The figure has been revealed in a Tusla report to the Dáil Public Accounts Committee.
Between 2022 and 2025, 2,530 who were alone and seeking asylum were referred to Tusla.
Of those, 293 were "deemed ineligible" for its services, and "referred back to the International Protection Office".
Last year alone there were 768 referrals, of which 288 underwent eligibility assessments and 141 were found to be over the age of 18.
The child and family agency says the average time these adults were incorrectly believed to be children, and were possibly living in children's accommodation was 57 days.
It added that age assessment in relation to unaccompanied minors has been an issue of significant risk in recent years, according to the Irish Times.

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