Digital radio listening grew at a record rate this year, with audience gains for the BBC's digital stations and commercial offerings including NME Radio and Absolute Radio Classic Rock.

Digital platforms, including digital audio broadcasting (DAB) radio, digital TV and online accounted for 24% of all radio listening in the first three months of this year, according to Rajar figures published today, up from 20.9% in the previous quarter and 20.1% in the same period in 2009. The gains were hailed as "a real milestone in the UK's transition to a digital future".

DAB radio remains the digital platform of choice with 15.1% of listening, followed by digital TV (4%) and the internet, with 2.9%.

The biggest year on year gains in the commercial sector were seen at Absolute Radio Classic Rock, up 37.1% to a weekly reach of 255,000 listeners, NME Radio, up 16.5% to 226,000, and Jazz FM, up 15.4% to 471,000 listeners. Another digital-only station, Absolute 80s, debuted with an audience of 264,000.

The BBC's under-threat 6 Music grew its audience by 47.2% on the previous quarter and 50.2% year on year to 1.023 million.

Other BBC digital-only stations showed big gains, if not quite on the same scale achieved by 6 Music.

Speech station BBC Radio 7 broke through the 1 million barrier, up 12.7% on the previous quarter and 6.6% year on year to 1.049 million. 5 Live Sports Extra was up to 685,000, from 642,000 12 months ago, and 1Xtra increased its weekly reach to 663,000, up 24.9% on the previous three months.

But the gains were not repeated at the other BBC digital service under threat, the Asian Network, which slipped back to 357,000 from 360,000 the previous quarter and 405,000 a year ago.

Planet Rock, this week named Sony digital radio station of the year for the second time, averaged 694,000 listeners, down marginally on the previous quarter but up 3% year on year.

Ford Ennals, chief executive of digital radio switchover body, Digital Radio UK, said: "These are extremely encouraging results and represent a real milestone in the UK's transition to a digital future for radio. 

"Over 40% of listeners now listen to digital radio every week and digital radio's share of listening is almost a quarter.  We are seeing growth right across the board – across all platforms, both year on year and quarter on quarter, and across commercial radio and the BBC, which both recorded strong digital listening growth."

The previous government set a target of 2015 for digital radio switchover, as outlined in the Digital Britain report, but only if 50% of radio listening was via digital platforms by 2013.

Bauer Media's The Hits remains the most popular commercial digital-only station, up 4.4% on the previous three months but down 18.8% year on year to 1.055 million. Bauer sister station Smash Hits Radio was also down, 0.6% on the previous quarter and 14.4% year on year to 853,000.

Other Bauer digital stations include Q, down 23% year on year but up 5.5% on the previous quarter to 231,000, and Heat, which was steady on the previous three months and up 5.7% year on year to 447,000. Global Radio's Chill lost around 20% of its audience both quarter on quarter and year on year, to 160,000.

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