Calderdale and Huddersfield NHS Trust was hit hard by winter pressures this year, figures show.
NHS England data, from December 3 last year to March 3, has revealed how acute hospital trusts coped over the colder months, based on occupancy levels and other key indicators.
General and acute wards at Calderdale and Huddersfield NHS Foundation Trust were 90.7 per cent full on average, well above the safe limit of 85% recommended by the British Medical Association.
On its busiest day, occupancy hit 96.2 per cent.
Across England, average occupancy was 93.5 per cent.
According to NHS Improvement, occupancy rates of 92 per cent and above lead to significantly worse A&E performance.
Dr Nick Scriven, president of the Society for Acute Medicine, said it was unacceptable to continue to expect hospitals to manage "on shoestring budgets and with depleting workforces".
He said: "For those working at the sharp end of the NHS the figures are no shock.
"Our hospitals have been on a knife edge for more than 18 months now, with staff run ragged trying to keep them safe.
"We have seen a year-on-year reduction in the beds available to care for acutely unwell people in hospitals, despite an ever-increasing need from an ageing population."
On average, there were one escalation beds in use each day at Calderdale and Huddersfield NHS Trust.
These are temporary beds set up during periods of intense demand, often in corridors or day care centres. Staff opened eight such beds when pressure was at its highest.
According to healthcare workers union Unison, cuts to social care budgets have led to a growing problem of long-stay patients - which can impact the ability of hospitals to accommodate urgent admissions.
On a typical day at Calderdale and Huddersfield NHS Trust, 260 patients had been in hospital for a week or more , taking up more than 40 per cent of all occupied beds.
Of these, an average of 86 patients had been in hospital for at least three weeks.
Unison head of health, Sara Gorton, said: "Although this winter's weather has been relatively mild, there has been no let-up in the pressures facing patients and staff, laying bare serious underlying problems."
She added: "Meanwhile, ambulance crews are tied up with handover delays rather than being where they and the public want them to be - responding to 999 calls and saving lives."
A total of 8,757 patients were taken by ambulances to Calderdale and Huddersfield NHS Trust over the winter months.
Delays left 535 patients waiting 30 minutes or more before they could be transferred to the care of A&E staff.
Of those, 17 patients waited for more than an hour before they were admitted. The NHS says a delay of just 15 minutes is a potential threat to life.
NHS England insisted ambulance services were improving, with crews responding to life threatening calls faster and experiencing fewer delays at A&E.
It added that staff has been "working incredibly hard throughout winter" to provide the best care for patients.