Tens of thousands of patients were waiting for routine treatment at the Royal Surrey County Hospital in October, figures show.
The Nuffield Trust think tank said progress on getting through the planned treatment backlog has "stalled yet again", as the NHS comes under severe strain.
NHS England figures show 29,535 patients were waiting for non-urgent elective operations or treatment at Royal Surrey County Hospital NHS Foundation Trust at the end of October – down slightly from 29,697 in September, and 37,955 in October 2024.
Of those, 678 (2%) had been waiting for longer than a year.
The median waiting time from referral at an NHS Trust to treatment at the Royal Surrey County Hospital was 14 weeks at the end of October – the same as in September.
Nationally, an estimated 7.4 million treatments were waiting to be carried out at the end of October, relating to 6.2 million patients. It was up slightly from the number of treatments at the end of September.
Just over 2% of people on the list for hospital treatment had been waiting more than 52 weeks in October.
The Government and NHS England are aiming to bring this figure to under 1% by March 2026.
It comes as the NHS is grappling with the threat of resident doctors going on strike next week in a dispute with the Government over pay and jobs.
Health Secretary Wes Streeting has offered the British Medical Association a last-minute deal in the hope of avoiding a five-day strike, which starts next Wednesday.
The doctors' union has agreed to put the offer to members over the coming days. The offer includes a fast expansion of specialist training posts as well as covering out-of-pocket expenses such as exam fees, but does not include extra pay.
Mr Streeting said: "I urge resident doctors not to inflict further damage on the NHS, vote for this deal, and call off the Christmas strikes."
Separate figures show 1.8 million patients in England were waiting for a key diagnostic test in October – a rise on 1.7 million in September.
At the Royal Surrey County Hospital, 7,256 patients were waiting for one of 11 standard tests, such as an MRI scan, non-obstetric ultrasound or gastroscopy at this time.
Of them, 2,143 (30%) had been waiting for at least six weeks.
Other figures show cancer patients at the Royal Surrey County Hospital are not being seen quickly enough.
The NHS states 85% of cancer patients urgently referred by a GP should start treatment within 62 days.
But NHS England data shows just 83% of patients urgently referred by the NHS who received cancer treatment at the Royal Surrey County Hospital in October began treatment within two months of their referral.
Sarah Scobie, Nuffield Trust deputy director of research, said hospitals are facing "extraordinarily" high rate of hospital admissions for flu.
"In the latest monthly data, progress on getting through the planned treatment backlog has stalled yet again – this reflects an NHS under severe strain and struggling to recover to the standards that the public expect.
"Our analysis of the Autumn Budget shows that growth in NHS spending is comparable to the slow growth seen during 2010s austerity.
"Such tight constraints will make it very difficult for the NHS to do everything asked of it, especially in the face of mounting problems like staff strikes and flu."




