The single largest unpaid bill was £66,256, owed to Guy’s and St Thomas’ in London, ahead of £53,844 at Imperial College Healthcare.Among the 66 trusts that gave figures for every year, the value of maternity charges raised against overseas visitors rose by more than a fifth, from £13.4million in 2023/24 to £16.4million in the year to March 2026.York and Scarborough Teaching Hospitals admitted that some patients will be chargeable but were never identified, and that their number is unknown.Under NHS charging rules, overseas visitors not entitled to free hospital treatment must pay, but maternity care must never be withheld because a woman cannot pay in advance.A Department of Health and Social Care spokesman said: “Overseas visitors – and those who are not lawfully settled here – are required to contribute towards any treatment they receive on the NHS.”The NHS recovers tens of millions of pounds every year from overseas visitors, and every NHS Trust is legally responsible for recovering these costs from chargeable patients.”