New figures revealed that on January 1, 98 per cent of the 453 beds across adult and paediatric general and acute wards at Barnsley Hospital NHS Foundation Trust were occupied.
Of the occupied beds, 438 were for adults beds and seven for children.
A further 22 of 24 critical care beds were occupied.
NHS national medical director for England Professor Sir Stephen Powis said: “We knew this winter would be one of the most difficult in the history of the NHS and I want to thank staff for all their hard work in caring for and treating so many patients while dealing with record demand on services, including the enormous pressure from flu and Covid.
“The plans we announced last autumn will help ensure we are in the best place possible to provide care for patients at this incredibly challenging time.”
Ambulance delays at A and E departments across the country also reached a new high in the week to January 1.
More than a quarter of patients waited over an hour to be transferred, while 44 per cent of handovers took longer than 30 minutes.
At Barnsley Hospital, 40 per cent of the 463 ambulance arrivals took more than an hour, while 57 per cent waited 30 minutes or more.
NHS targets state trusts should complete 95 per cent of all ambulance handovers in 30 minutes, with all conducted in less than one hour.
A handover delay does not always mean a patient has waited in the ambulance as they could have been moved into an A and E department but the handover was not completed.
The latest NHS England figures also show there were 57 flu patients being treated by Barnsley Hospital NHS Foundation Trust as of January 1 - up from 32 the week before.
All of them were in general and acute wards.
It represents an increase from the start of the winter - no flu patients were being cared for at Barnsley Hospital on November 14, the earliest available figures for this winter.
Health research centre the King’s Fund said: “The NHS was struggling before the rise in flu cases, so there is a lot more needed in resources, funding and investment so that services can deal with the same problems should they arise in the future.”
While the number of patients at Barnsley Hospital with Covid has more than doubled in the latest seven-day period.
There are 46 patients at the site with the virus according to the government’s website - the highest figure since last July.
It’s a 117 per cent increase on the previous week’s figures.
There’s also one patient on a ventilation bed.
A hospital spokesperson told the Chronicle: “Like other hospitals across the country, Barnsley has been facing very high numbers of people requiring admission to hospital.
“This is due to a number of factors such as the prevalence of respiratory illness.
“There is a well-practiced process for managing high bed occupancy levels that involves staff across the trust reviewing admissions, discharges and the inputs required to support people’s recovery.
“We thank all our staff who continue working tirelessly to support patients.
“The NHS always prepares extensively for winter pressures, to ensure life-saving care continues and to minimise disruption to patient care.
“If you do need medical help, please continue to use 111 online and in emergencies call 999.”