Data from NHS England shows just 81.1 per cent of A&E patients at Leeds Teaching Hospitals NHS Trust were seen within four hours in November - down from 83.5 per cent in November 2018.
The national average time from arrival to admission, transfer or discharge for acute hospital trusts is 81.4 per cent.
The target across the country is 95 per cent, and for the first time every major A&E unit in England has failed to hit its four-hour waiting time.
There were 5,117 instances where there was a waiting time at A&E of more than four hours from arrival to admission, transfer or discharge at Leeds General Infirmary and St James's Hospital last month.
A spokesperson for Leeds Teaching Hospitals NHS Trust said: “Like the rest of the UK, we are seeing a year-on-year growth in the numbers of patients attending for urgent care and an increase in the complexity and acuity (severity) of illness."
Across the country, there were 88,923 patients waiting more than four hours from a decision to admit to hospital admission, 64 per cent higher than the same month last year when it was 54,373.
Of these, 1,112 patients waited more than 12 hours compared with 258 in November 2018, a 331 per cent rise.
The number of people waiting for treatment, such as knee and hip replacements, was also at its highest-ever level - 4.45 million - in October.
Just 84.7 per cent of patients are starting treatment within 18 weeks against a target of 92 per cent.
Targets on how long people should wait for cancer treatment also continue to be missed, the data shows.
Nuffield Trust chief executive Nigel Edwards said: "Returning to Downing Street, Boris Johnson has been met by an immediate reminder of the grim winter his Government faces in the English NHS.
"The November figures show the number of patients waiting on trolleys is at its highest level ever, a very worrying sign with the coldest months still to come.
"For the first time, not one single major A&E department in England met the current four-hour waiting time target.
"Figures for the first week of December suggest what may be driving this, showing bed occupancy at 95 per cent, a level which will make it near impossible to admit many patients in need on to the right ward.
"To tackle this, the new government really will need to deliver the 50,000 nurses promised - even if this means more reliance on migrants than they've said.
"We need a long-term commitment to funding for NHS infrastructure, not one-off announcements.
"And we need to finally see the overhaul of England's failing social care system that has been pledged so many times."
Dr Rebecca Fisher, a GP and senior policy fellow at the Health Foundation, said the figures show the 'task ahead for the next government'.
Dr Fisher said: "Without more money and more staff, it will be challenging for the NHS to reverse the current deterioration.
"Our analysis shows that the NHS will need an increase of £20 billion by 2023-24 just to maintain standards of care but more will be needed to improve services.
"The £18 billion extra promised by the Conservatives during the election campaign falls short of what is needed."
A spokesperson for Leeds Teaching Hospitals NHS Trust said: “Our performance against the ‘four hour standard’ in the Emergency Departments is in line with the national average for hospitals of our size and complexity.
“Like the rest of the UK, we are seeing a year-on-year growth in the numbers of patients attending for urgent care and an increase in the complexity and acuity (severity) of illness.
“We continue to work with our partners across the NHS and social care to reduce waiting times in our Emergency Departments and improve flow out of hospital as soon as a patient is ready to go home. Our staff are working hard to maintain safe services and ensure we deliver the best care to our patients and their families.”
Dr Katherine Henderson, president of the Royal College of Emergency Medicine, said: "Performance continues to plummet to record lows despite the best efforts of staff.
"Our hospitals are near full and the number of patients needing to be admitted to a bed continues to rise year on year.
"Thousands of patients are staying longer than 12 hours in emergency departments each week.
"Patients are suffering as a result of years of under-resourcing. We welcome the promises made on health spending by the new government.
"For the sake of our patients, these promises must be turned into actions, and now is the time to act."