Councils dished out parking fines at the rate of one every four seconds last year, it has been revealed.
Local authorities issued around 7.8 million parking penalty charge notices (PNCs) in 2013. amounting to £255 million in fines, according to research by Churchill Car Insurance.
And the figures could be even higher, as Churchill's statistics relate to responses from only 187 of the 435 UK councils contacted for data under the Freedom of Information Act.
According to Churchill, Westminster council issued the highest number of PCNs among responding councils and generated the most in potential revenues last year.
Westminster handed drivers 455,390 parking fines, worth more than £24 million.
The top 13 locations for total PCNs issued last were all London boroughs. Outside London, Cardiff council issued the highest number of parking fines at 56,766 and North Somerset generated the most revenue at £2.25 million.
Despite 7.8 million tickets being issued in 2013, just 445,818 PCNs were successfully appealed against during the year, roughly equivalent to 6% of the total PCNs issued. The highest number of appeals was in Haringey in north London, where 21,617, or 13 % were successfully challenged.
"The capital is extremely congested so we'd expect to see a higher number of restrictions in place and penalties being issued. However, there is a fine line between fair and opportunistic that councils shouldn't be tempted to cross."
Communities Secretary Eric Pickles said: "The law is clear. Councils should not use parking as a tax or cash cow, and we are currently looking into the potentially illegal use of councils' parking contracts.
"Councils should open their books so that any interested members of the public can scrutinise local parking practice and expose any dodgy deals."
He went on: "This Government is reining in over-zealous parking enforcement and unfair parking practices in England, with the levels of parking penalty charges being kept under review.
"We have scrapped Whitehall planning policy that encouraged councils to hike parking charges and removed restrictions around the provision of off-street parking spaces. We also recently announced further reforms including stopping CCTV being used for on-street parking enforcement and reviewing unnecessary yellow lines."