More than 1.7 million motorists' details have been handed over to private parking firms by the DVLA in just three months, according to latest figures.
The Driver and Vehicle Licensing Agency (DVLA) gave 1.74 million car owners' details to parking companies between April and June this year, equating to roughly 19,000 a day.
The DVLA charged the companies, which use the information to chase drivers for parking payments, £2.50 each time.
The RAC Foundation found there had been a 64% surge in the number of details being handed over to parking firms when compared with the same period last year. If the amount of data handed over by the DVLA between April and June was replicated across the remaining three quarters of this year, the annual total would be seven million details, up from 4.7 million in 2016/17.
ParkingEye Ltd obtained the largest amount of information at 570,000 records, Smart Parking received the second most at 125,000 and Euro Car Parks third, at 118,000.
Parking companies use the information to chase vehicle owners for alleged infringements in privately run car parks – including those at hospitals, pubs, hotels, supermarkets and shopping centres – often sending tickets asking for up to £100. See our Fight Unfair Private Parking Tickets guide for more information.
Which companies are allowed to ask for my details?
To access DVLA data, parking firms must be members of an accredited trade association. There are currently two of these: the British Parking Association and the International Parking Community.
To be able to access the data, private parking companies must follow the association's code of practice and allow cases to be referred to an independent appeals process.
If you've been given a parking ticket, here's how to check if the company is a member of an association that can ask the DVLA for your details.
RAC Foundation: 'Self-regulation has not worked'
Motoring charity the RAC Foundation dug through the latest DVLA data a week after Conservative MP Sir Greg Knight introduced a proposal to create a single nationwide legally binding code of conduct for car parking firms.
RAC Foundation director Steve Gooding said: "Self-regulation of the private parking sector has not worked – even many of the big companies acknowledge that – and we are delighted that [the bill] will create a single, binding code of conduct, something we have campaigned for over several years.
"Private parking has turned into an industry worth hundreds of millions of pounds with many firms relying on enforcement as their only way of making money.
"No wonder the DVLA is now being inundated annually with many millions of requests for vehicle keeper data so drivers can be sent penalty tickets on often dubious grounds."
A DVLA spokesperson said: "We take our responsibility to protect information extremely seriously and we have robust safeguards in place to ensure data is used correctly. Our data release charges are set to recover the cost of providing the information."