The data was collected for hospitals across the country through a Freedom of Information request, and found that more than £160million was made in 2015/16.
Hillingdon Hospitals NHS Foundation Trust was a close second with a large majority of the money being paid by patients and visitors.
'The NHS is clearly underfunded'
Katherine Murphy from the Patients Association, a charity which represents patients of health services, said: “The shocking reality about car parking charges is they are taking money from the sick and vulnerable to top up NHS coffers.
"This is not what parking charges should be used for.
“The NHS is clearly underfunded, but the onus on meeting the funding crisis should not be shouldered by the sick, injured and vulnerable.
“We are not talking about insignificant amounts of money either.
"It is alarming that trusts think it is okay to charge people so much money for visiting a hospital, as it makes patients question the values of the people leading the organisation.
“We take a very clear line that car parking fees need to be scrapped or strictly capped.”
Patients pay most at Hillingdon
Hillingdon Hospitals NHS Foundation Trust raised £1,641,232 in 2015/16, with £1,341,844 being coughed up by patients and visitors, while staff paid £299,388.
London North West Healthcare NHS Trust made £968,170 over the course of the year, but a further £1,262,194 was kept by a management company under a private finance initiative arrangement.
The figures revealed almost half of all NHS trusts charge disabled people for parking in some or all disabled spaces.
Heart of England NHS Foundation Trust topped the tables when it came to parking income, making a massive £4,841,108 over the year.
Patients paid forward £3,465,357 and a further £1,375,751 came from staff.
Freedom of Information requests were sent to 120 trusts in England, with 89 responding.
According to the Mirror, if all 120 trusts had responded the income rates would total around £160million.
Ms Murphy said fines were a burden on the sick: “It is not right that fines should be so heavy handed on sick and disabled patients.”
A statement from Hillingdon Hospitals said: "The trust’s parking charges cover the costs of parking management at both of its hospitals and any small surplus made is ploughed back into the trust.
"The trust complies fully with the Department of Health's car parking management guidance.
"We provide a range of parking concessions including: free parking for Blue Badge holders; discounted weekly (£1.71 per day) and monthly (82p per day) parking permits, as well as reduced cost parking for cancer patients (£1 a day) and parents of children with oncology needs.
"We also offer free, 20-minute drop-off points and free exit to patients with cancelled appointments."
Nigel Myhill, Director of Estates & Facilities at London North West Healthcare, said: “It would be wrong to use money allocated for healthcare services and patient care to pay for the maintenance and upkeep of parking facilities.
"The tariffs are agreed with APCOA, the private company that runs the carparks on our behalf and are aligned to those of neighbouring hospitals. Any surplus made from parking charges goes back into the hospital.
“We understand that parking charges are unpopular and we offer a range of concessions to make it easier for our patients and visitors. In line with Department of Health guidance, discounted passes are available for patients and families who need to visit our hospitals regularly or for long periods.
"Three, five and seven day passes are available as well as reductions for renal patients. Free parking is available for Blue Badge holders (when parked in a designated bay) and we will shortly be introducing further concessions which include much reduced parking rates for patients receiving cancer treatment at £1 per day.”
Getwestlondon has approached Chelsea and Westminster trust for comment.
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