Parking management firms requested the keeper records of 1.7m vehicles in the second quarter of this year, according analysis of Government data by the RAC Foundation.
The total is 20 per cent up on last year and the highest on record for a single quarter.
The increase coincides with the ban on clamping vehicles on private land. The law that prohibited it allowed parking companies to pursue vehicle owners for unpaid charges.
Under the legislation, companies can request records from the Driver and Vehicle Licensing Agency, at a cost of £2.50 a time, to chase up payments for alleged infringements in private car parks such as at shopping centres, leisure facilities and motorway service areas.
Each penalty charge can cost drivers up to £100.
A Private Member’s Bill from Conservative former minister Sir Greg Knight, which the Government supports, would see the introduction of a code of conduct for private car park operators. It is currently at the report stage in the Commons.
Steve Gooding, director of the RAC Foundation, said: “The private parking industry never ceases to surprise, or dismay. Just when you think that we must have peaked, the number of tickets keeps going on up.
“Parking should be an inconsequential act with the system working for both drivers and land owners. But yet again we see numbers that suggest the relationship is going badly wrong.”
The RAC said that in half the cases where a driver had appealed against a fine, the ticket was cancelled.
Mr Gooding said: “It is surely inconceivable that 18,000 drivers a day are knowingly setting out to ignore parking rules. Are thousands of drivers really failing to understand the rules? Or might many be being pursued on the flimsiest of grounds in the hope that they won’t put up a fight?
“Frankly we think Sir Greg Knight’s Private Member’s Bill can’t come into law too soon, bringing the era of self-regulation of private parking to a close with firms having to abide by a code of practice signed off by ministers.”
The DVLA agency says it does not make any money from supplying drivers’ details to parking firms.