The claim: Labour could make car parking free at NHS hospitals for £162m.

Reality Check verdict: The £162m is derived using an extrapolation that is unreliable. The Barnett formula is also likely to add about another £30m, and logistical costs could add more.

Labour has promised to make car parking at NHS hospitals in England free, if it wins the election.

Hospital car parking fees were abolished in Scotland and Wales in 2008, although a small number of hospitals still charge as they remain tied in to contracts with private companies that manage their parking facilities. Fees may be charged in Northern Ireland.

In England, whether to charge fees is a decision for individual trusts, with some making parking free for particular patients such as cancer patients or those using dialysis, or for parents staying overnight with their children.

Jeremy Corbyn told BBC News: "This would cost £162m.

"Going to a hospital shouldn't incur an additional charge. In reality it's a charge on sickness."

That figure is based on Freedom of Information requests made by the Press Association at the end of last year.

Responses from 89 of the 120 NHS trusts in England showed they had made £120,662,650 in parking fees in the financial year 2015-16.

Labour has assumed that the remaining trusts would have had the same average parking fees as those that responded, and extrapolated to reach the figure of £162m.

That is not statistical best practice, especially because some of the bigger trusts, such as the Oxford University Hospitals NHS Foundation Trust, did not supply 2015-16 figures.

The previous year, that trust alone made £3,728,000 in parking charges, so the overall figure for England could be considerably higher.

Even though fees generally aren't charged in Scotland and Wales, if extra money is to be spent on car parking at hospitals in England then money will also have to go to the other nations under the Barnett formula, which Labour says would take the bill up to £190m.

There could be additional charges on top of that, as hospitals that currently contract out their car parking would have to maintain their own car parks and find a way to patrol them to ensure that hospital car parks weren't being filled up by people who were not using the hospital.

By the standards of health spending, £162m is pretty cheap, approximately equal to the amount it costs to run the NHS in England for 12 hours.

Nonetheless, it is a big issue for patients and visitors who have to pay to park at hospitals.

NHS Digital releases average parking costs at hospitals, although not the overall amounts raised.

A small number of hospitals charge as much as £3 an hour for parking.

There was also a report from the RAC that criticised hospital parking in England for being "unreasonably stressful".

It said too many car parks made users decide in advance how long they would need to park for, so that they often either overpaid or had to leave appointments to put more money in the meter.

Labour also highlighted some NHS staff having to pay to park at the hospitals where they worked.

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