It means the Daily Mail and The Mail on Sunday have overtaken The Sun and The Sun on Sunday for the first time in 42 years.
The Daily Mail sold an average of 948,000 copies a day through UK retailers in May, the highest Monday to Saturday sales of any title. Meanwhile, DMG said The Mail on Sunday beat The Sun on Sunday, selling an average 817,000 copies a week.
News UK, owner of The Sun and The Sunday on Sunday, now reports its circulation figures privately, following a change to ABC rules, while the Daily Mail and The Mail on Sunday’s figures continue to be published and available publicly.
Daily Mail editor Geordie Greig described it as an “historic moment”. He said: “I am immensely proud and delighted that the Daily Mail has become Britain’s biggest-selling newspaper.”
Find out the latest ABC circulation figures