After being acquired by Global for an undisclosed sum, Atlantic will be rebranded progressively over the coming months as Heart Cornwall, supported by a promotional campaign guiding listeners through the change.
Breakfast and drivetime shows will still be produced in the south west, while local news will continue on the hour and advertising will be sold locally.
Further investment will be made in the local sales teams to upgrade their systems and hardware later this year. Sales staff will remain at Atlantic's St Agnes offices, but programming will transfer to the Heart broadcasting centre in Exeter.
The move extends Heart into Cornwall and strengthens its position as the UK's largest commercial radio network, covering regions including London, Bristol, the West Midlands, Kent, Sussex, Hampshire, Dorset, Devon, Norfolk and Suffolk.
According to the latest radio audience data released by RAJAR, the Heart network reaches 7.5m people every week, broadcasting a total of 53m hours every seven days.
Global Group founder and executive president Ashley Tabor said that it is an "exciting development" for Heart since the network merged and went nationwide in January 2011.
He added: "We've wanted to achieve this for some time and we warmly welcome Cornwall to the Heart family!"
Atlantic's deputy chairman Jeremy Scott said: "We are delighted to conclude the sale of Atlantic to Global Radio. Very few local stations get the invitation to join a network like Heart, where they care about the localness of their output and offer high quality network programming in a challenging new digital era.
"For listeners and advertisers right across the county, it'll soon be time to upgrade - to the brand new Heart Cornwall."
The core Heart network features various high-profile presenters, including Emma Bunton, Toby Anstis and Jason Donovan; complemented by programming aimed at each local area.
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