President Donald Trump paid no federal income taxes in 10 of the past 15 years, according to a report in The New York Times.
The Times said the disclosure comes from tax return data it obtained extending over 20 years.
Mr Trump, who has fiercely guarded his tax filings and is the only president in modern times not to make them public, paid 750 US dollars (£578) in taxes to the federal government the year he was elected, 2016, and 750 dollars again his first year in office.
The report comes at a pivotal moment ahead of the first presidential debate on Tuesday, and weeks before a divisive election.
A lawyer for the Trump Organisation, Alan Garten, told the Times that “most, if not all, of the facts appear to be inaccurate”.
Mr Garten said in a statement to the news organisation that the president “has paid tens of millions of dollars in personal taxes to the federal government, including paying millions in personal taxes since announcing his candidacy in 2015”.