A third of hospitals in England put up car park charges last year, with trusts raking in more than £254 million from parking in 2018/19.
A study for the PA news agency found that many patients and visitors said they felt ripped off, with almost 9 out of ten (86%) saying parking added to the stress of a hospital visit.
For the survey, 7,883 patients and visitors who had used a hospital car park in the last two years were questioned, and financial data was gathered from 144 NHS trusts.
Overall, 47 NHS trusts increased their charges between 2017/18 and 2018/19, typically by 10%.
Only England's hospitals routinely charge for parking – car parks are largely free in Scotland, Wales and Northern Ireland.
For those trying to park at hospitals in England, 32% said they struggled to find a space, while 10% said there was a lack of disabled provision. Other common complaints included long queues and meters that did not work.
Almost half (49%) said nobody should have to pay for parking at hospitals with the government footing the bill instead, while 46% thought visitors should have to pay, 12% said patients and 8% said hospital staff.
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Comments from those questioned about hospital parking charges included "a rip-off", "too expensive", "extortionate", "astronomical" and "exorbitant".
A spokeswoman for the Patients Association said: "Charges for car parking at hospitals are a charge on people who are unwell, levied on them because they are unwell. We believe that patients should not be effectively charged for being ill.
"Practical arrangements to prevent car parks being used by other motorists can and should be installed, as they are at supermarkets, hotels and so on."
Deputy chief executive of NHS Providers Saffron Cordery said increases in the cost of parking were frustrating, but added: "Car parks are expensive to run for the trusts that own them.
"These parking facilities must be maintained, lit well, and secure. Parking facilities must also provide good access for patients, families and staff.
"All charges by trusts for parking cover the day-to-day running of car parking at the hospital, with any surplus reinvested back into wider services for patieRead More – Source