Jazz FM will broadcast again in London and the North-West as a DAB-only station, subject to agreement from regulator Ofcom later this year.
GMG Radio converted the station's old 102.2 FM frequency to Smooth Radio three years ago, reducing its jazz content, but keeping Jazz FM online.
The company will use two spare Real Radio platforms to house the new stations in London and the North-West.
However, GMG said it believes Jazz FM is a niche listen and with the closure of GCap's TheJazz, there is an opportunity to provide listeners with jazz 24 hours a day, rather than squeeze it into Smooth's playlist at night time.
John Myers, GMG Radio chief executive, said: "DAB has come a long way in recent years and we are confident that Jazz FM has a promising future on a digital platform.
"We have always carried on with Jazz FM online but we now hope that the gap left by The Jazz will enable us to win an increased audience to this new service."
Earlier this month, GCap unveiled plans to dispose of the three non-London Xfm stations, close digital-only stations TheJazz and Planet Rock, and sell its shareholding in the Digital One DAB multiplex.
Jazz FM's line-up and full programme schedule details will be announced at a later date.