The European Court of Auditors says the European Commission is not moving fast enough to recover EU money that is not spent in accordance with the regulations.
EU auditors said, in a report published on Tuesday, that often more than a year or more passes between the end of subsidized measures and the recovery of funds.
A further three to five months elapsed before the funds were reimbursed, the report added. In up to 8% of cases, claims are even waived completely.
However, the commission ensures that irregular expenditure is recorded accurately and quickly, the report said.
Some 4.2% of the EU budget in 2022 was not spent in accordance with the rules, according to data. Irregular expenditure totalling €14 billion ($15 billion) was reported across all policy areas between 2014 and 2022.
The recovery of irregular amounts is an important instrument, for example to prevent further irregularities, the report said.
"The swift recovery of misspent EU funds should be pursued with the utmost vigour," said Jorg Kristijan Petrovic, responsible for the topic at the European Court of Auditors. "The EU owes this to taxpayers. Failure to recover funds would severely damage citizens‘ trust in the EU."
EU funds from the common budget of the member states are available across all policy areas, from agricultural subsidies to cohesion policy payments and beyond, to help structurally weak regions grow and minimize economic and social differences.
But only 20% of the funds are spent directly by the European Commission, while 70% is administered jointly with the member states and 10% by international organizations or third countries.
Under certain conditions, irregular expenditure can be recovered wholly or in part by the commission or the EU countries or organizations who had the funds.