The four-week national activity aims to cement the Global Radio-owned brand as the “relaxation station”, where listeners can tune in to unwind.
Posters will appear in train stations, on bus rears and on bus sides across the country. The outdoor campaign will also be supported by press and online activity.
Meanwhile, a branded triple-CD set of piano music will be released for sale and will be supported by a separate television and press campaign.
The push comes a month after Rajar listening figures showed the station added 303,000 new listeners in the three months to 30 June to register 5.7m listeners per week.
Classic FM, which Global claims is the “largest” commercial radio station in the UK, features a number of veteran radio broadcasters and celebrities as presenters, including Blur bassist, Alex James, Myleene Klass, Simon Bates and the actor Tony Robinson.
Giles Pearman, marketing director at Global Radio, says the campaign “underlines Global Radio’s continued commitment to invest in its radio brands”.
The radio group has launched campaigns for its 95.8 Capital FM and LBC stations this year.
It also recently featured ex-Spice Girl and Heart presenter Emma Bunton in a campaign to promote the rebrand of 12 more stations to Heart in the south of England, which followed the 21 renamed earlier this year.