Hundreds of thousands of young adults in the UK are sitting on savings accounts they do not know exist, with more than £1.6bn lying unclaimed in matured Child Trust Funds belonging to people aged between 18 and 23.

HM Revenue and Customs figures show 758,000 matured accounts had gone unclaimed as at 5 April 2025, with an average balance of £2,242 for account holders in that age bracket. More than 60% of those accounts had matured more than a year earlier. HM Treasury put the total unclaimed sum at more than £1.6bn in June 2026.

The money belongs to a generation born between 1 September 2002 and 2 January 2011, all of whom were eligible for a Child Trust Fund — a long-term, tax-free savings account seeded with at least £250 of government money, rising to £500 for children in low-income households or local authority care. Around 6.3 million accounts were opened and roughly £2bn of public money paid into them before the scheme was closed to new entrants in 2011 and replaced by the Junior ISA.

Account holders take control at 16 and can withdraw or reinvest the money from their 18th birthday. Nearly 2.3 million accounts had matured by April 2025, and the remainder will mature by 2029 as the youngest eligible holders turn 18.

The scale of the shortfall stems in part from how the accounts were set up. More than a quarter were opened automatically by HMRC after parents or guardians failed to act on vouchers posted to them — an early sign of the tracing problems now emerging at maturity. Others go unclaimed because holders have moved address, forgotten the account exists, or have deliberately left the money invested.

"If you're between 18 and 23, you could be sat on a savings payout and not even realise it," said Angela MacDonald, second permanent secretary and deputy chief executive at HMRC.

The sums involved are not trivial. HMRC data shows 27,000 unclaimed accounts hold at least £10,000, of which 7,000 contain £25,000 or more. Analysis of the same figures by the investment platform AJ Bell found £899m sat in accounts that had matured more than a year previously, and around 280,000 pots holding more than £1,000.

Campaigners warn the value of that money can erode while it sits untouched. No further contributions can be made once an account matures, and funds are typically moved into a default account paying a low rate of interest. A 2023 Public Accounts Committee report indicated many providers charge around 1.5% a year to manage passive portfolios, against roughly 0.25% on a modern Junior ISA platform.

Ministers have stepped up efforts to reunite holders with the cash. In April 2026 the Treasury announced HMRC would write to thousands of 21-year-olds — a cohort chosen because their addresses are most likely to be current through PAYE or student finance records. A Child Trust Fund Taskforce bringing together the Treasury and providers including Nationwide, HSBC UK, OneFamily, Coutts, Sheffield Mutual and the Coventry held its first meeting on 29 June.

Separately, the charity Contact estimates more than 80,000 disabled young people risk being locked out of some £210m because families in England and Wales must apply to the Court of Protection to access the funds on their behalf. The Ministry of Justice says waiting times have fallen from about 24 weeks to roughly eight, and several providers now allow access without a court order.

Anyone who thinks they may have an account can trace it free of charge:

HMRC stresses that genuine correspondence about Child Trust Funds arrives by post only. Any email, text or phone call is a scam, and paid claims firms — some charging £350 or a 25% cut — are unnecessary.