Euro car parks are being investigated for petrol forecourt parking charges.

Emma Cochrane, the CMA’s director of consumer protection, said receiving a parking ticket can be a stressful experience.

“Prices are high and often unpredictable, which makes it difficult for people to budget carefully,” she says.

“Parking companies must treat drivers fairly at all levels – and a clear and consistent appeals process must be at the heart of this.

“It is time all private car park operators comply with the Consumer Code or risk action from the CMA.”

In an open letter to private parking operators, the CMA has warned them to review their terms and conditions and make changes where necessary to ensure compliance with consumer law.

The CMA’s investigation into Euro car parks will focus on whether it is fair to drivers when they line up or use petrol pumps and other forecourt services such as car washes and an extensive appeals process.

It is in the evidence-gathering stage, and is scheduled to run until the spring of 2027.

Euro Car Parks has more than 3,000 facilities in the UK and Ireland, with more than two million cars parked every day, according to the company’s website.

The BBC has contacted Euro Car Parks for comment.

Simon Williams, head of policy at the RAC, said the CMA’s efforts were “a major step forward in ensuring drivers are treated fairly by private parking operators”.

He pointed out that the enforcement action will come before the government responds to the consultation to restore the private parking regulations.

“The CMA has shed much needed light on the appeals process and identified major issues that need to be addressed,” he said.

“We strongly hope that the code will give us one independent appeals body instead of the two we have now – for every two trade unions.