Tax breaks for owners of private jets registered for VAT in the Isle of Man increased to £100m last year, despite warnings from the European commission that the practice is a breach of EU laws.

The latest figure brings the amount of tax avoided on private jets to £940m since 2011. The Formula One champion Lewis Hamilton, who lives in the tax haven of Monaco, and oligarchs close to the Russian president, Vladimir Putin, are among those who have benefitted.

In 2018, the owners of 19 luxury aircraft applied for the maximum 20% VAT refund when importing their luxury aircraft into Europe, and all applications were granted, a freedom of information request has revealed.

The Paradise Papers investigation revealed in November 2017 that Manx customs and excise had allowed multimillionaires and big corporations to claim VAT refunds – worth 20% of the cost of the aircraft – on hundreds of luxury planes.

The Isle of Man puts its VAT receipts into a common pot with the UK, so any refunds granted are a loss to all British taxpayers.

Jet owners claimed back just under £100m last year. The figure is an increase on 2017, when the owners of 21 aircraft were refunded nearly £70m in total. The data show that since 2011, the Isle of Man has issued full VAT refunds to all applicants listed as requesting them.

In November 2018, Brussels launched infringement proceedings against the Isle of Man, describing the tax breaks as “abusive” and characterising them as “evasion”. The concern is that jet owners are choosing to import to Europe via the island, a British crown dependency, because they can avoid tax that would be payable in other EU countries.

“It is simply unacceptable that the super-rich do not pay their fair share of VAT on luxury goods, thereby contributing to lost VAT revenues for EU member States,” the European commissioner for economic and financial affairs, Pierre Moscovici, said at the time.

It is understood red flags had been raised as early as October 2017, when the commission began investigating tax breaks for yachts and jets in various European countries. That month, Moscovici wrote to the UK Treasury requesting information.

Far from closing down the allegedly illegal loophole, the Isle of Man has apparently kept it wide open. A promised review by the UK Treasury has never been published.

With the UK poised to leave the EU, it is unlikely the commission’s challenge will lead to court action. Ministers will have to decide whether to pull the Isle of Man into line with European laws or ignore them, and that decision will depend on factors such as whether the UK remains part of the EU customs union.

The European commission said it was “in contact with the UK authorities” and that it was considering its response to the latest letter from the Treasury.

In a statement, the Isle of Man Treasury said: “VAT law and the rules and policies in this area are highly complex. The Isle of Man follows the same policy, laws and rules as the UK in relation to the importation of aircraft and with a focus on the VAT treatment of aircraft leasing arrangements.”

• This article was amended on 9 April 2019 to clarify that the amount refunded to aircraft purchasers was the full VAT amount, not 20% of the total amount paid.