Easter vacationers should now be safer with hidden cars when hiring a car, say the competition authorities.
Action triggered by a car's review The rental industry, which many companies found, offered low prices by obscuring the main additional costs.
Around 30 leading British websites have now promised clear pricing including mandatory costs in offers.
Another 20 sites with 1
Consumer Protection Law requires transparent pricing, which includes all mandatory costs.
The UK's Competition and Market Authority (CMA) has monitored several improvements, highlighting charges such as fuel surcharges, young driver fees and off-duty pickup fees.
The CMA claimed that it had "significantly improved" the sector. Now it is said that it is taking enforcement action against car rental companies based overseas but selling directly to customers in the UK online.
"This move sends out a clear message: Just because a deal is not on British soil does not mean that the law" It applies when sold in the UK, "said Michael Grenfell, Director of Enforcement at the United Kingdom CMA.
The announcement comes as data from the UK's European Consumer Center between March 2017 and February 2018 showed an increase in complaints and 36% showed inquiries from UK consumers compared to last year
Complaints included hidden fees for fuel, high insurance surpluses and other hidden insurance costs.
Leon Livermore, of the Chartered Trading Standards Institute, said: "UK consumers have it. The CMA's guidelines and policies ensure that businesses are transparent and upfront so consumers can make informed choices , "