Hospitals in Birmingham were forced to spend £9.2 million over the past 12 months on caring for patients who did not need to be there – but had nowhere else to go.
The so-called "delayed discharges" occur when a patient is medically fit to leave hospital but are still occupying a bed.
It can happen when patients need to go into a nursing home or a care home, but there are no spaces available.
It might also mean a patient is capable of returning to their own home, but need to be provided with support there.
The delay is often caused because local councils do not have the resources to provide the care needed. This is sometimes known as "bed blocking".
In Birmingham over the 12 months up to the end of October, "acute" beds were used by a patient who didn't need them for a total of 30,473 days – each day means one bed was occupied by one patient unnecessarily for a day.
And the NHS says it costs an average of £303 for each day.
NHS figures also show that some hospitals are coming close to running out of beds.
Last week, 1,052 out of 1,058 beds were full at the Queen Elizabeth Hospital in Edgbaston, run by University Hospitals Birmingham NHS Trust. It means only six beds were free.
And 493 out of a total of 499 beds were in use at Walsall Healthcare NHS Trust, which runs Walsall Manor hospital. It again means only six were free.
A spokesperson for University Hospital Birmingham said: "The Trust is currently running at around 98 per cent capacity due to demand for our specialist services.
"Our bed capacity is effectively and closely managed through a 24/7 Ward View system which is visible to all wards across the Trust.
"Information from this in-house developed system is fed through in real time to the four bed meetings held between 7am and 9.30pm every day to ensure best use of resources and the most appropriate care, in the right setting, for our patients.
"We are satisfied that we are managing bed capacity in the most efficient manner possible given the current pressures, with no detrimental effect on the high standard of care delivered to all of our patients."
But the hospitals were coping better than some in other parts of the country.
Northampton General Hospital was completely full as was Kettering General Hospital.
And some hospitals just do not have enough money, according to a report by the National Audit Office, an official independent watchdog.
In the last financial year, which ended in April, hospital trusts nationwide went £843 million over budget in total. And the situation is not improving. The report said: "Trusts are increasingly unable to keep their spending within budget."
The National Audit Office named the trusts with the worst financial problems, which means they went more than five per cent over budget.
They include Walsall Healthcare NHS Trust, which is expected to overspend by £16.7 million this year.
They also include Worcestershire Acute Hospitals NHS Trust, which runs hospitals in Redditch, Worcester and Kidderminster, and is expected to go £31.3 million over budget this year.
The National Audit Office also named Burton Hospitals NHS Foundation Trust, which runs Queens Hospital in Burton, Staffordshire, and is expected to go £20 million over budget.
Heidi Alexander, Labour's Shadow Health Secretary, said: "This winter is going to be a very tough time for the NHS. Perhaps the toughest winter for a generation.
"Hospitals are likely to end the year more than £2 billion in the red. You have a shortage of doctors and nurses which is forcing hospitals to hire in expensive agency staff."