|Broadcast area||East Sussex and parts of West Sussex (as Heart Sussex) and Crawley and Surrey as Heart Sussex for Crawley & Surrey. Broadcasts to Chichester by DAB Radio.|
|Slogan||The Heart of Sussex on 102.4 & 103.5 & The Station for Sussex and Surrey|
|First air date||(as Southern Sound) 29 August 1983 / Re-branded 'Heart', 22 June 2009 / Heart Sussex for Crawley and Surrey, 26 July 2010|
|Audience share||12.9% (December 2009, :: RAJAR)|
|Website||Heart Sussex for Crawley & Surrey|
Heart Sussex (previously Southern FM, also operating as Heart Sussex for Crawley & Surrey in Crawley and Surrey) is an Independent Local Radio station which is owned by Global Radio (formerly GCap Media) and plays commercial, chart-oriented popular music. Broadcast and managed from studios and offices in Portslade, Brighton and Crawley, the station plays a mix of pop, rock and RnB with the overall tag line being 'The station for Sussex and Surrey' - replacing Mercury FM.
On 17 September 2008, it was announced that Southern FM was one of 30 local radio stations to face a re-brand to Heart within the next 18 months. Southern FM was rebranded as Heart Sussex on 22 June 2009. Mercury FM also merged with Heart in July 2010 to be re branded and re-launched as an sub-section of Heart Sussex operating as Heart Sussex for Crawley & Surrey or simply Heart Crawley & Surrey - sharing the same programming coverage.
The station launched as Southern Sound from the converted Rothbury Cinema in Franklin Road, Portslade. Under the leadership of managing director Keith Belcher and programme director Rory Macleod, early presenters included Sean Bolger, Louis Robinson, Stewart Macintosh, Vince Geddes, John Mann, Russ Williams and Becky Manesseh. The head of news at launch was Paul Woodley with a reporting team including Andy Steggall, Sue Trimingham, Sue Maskell, John Worthington, Andrew Winter and Cornelius Lysaght.
Tommy Boyd joined the station, initially as a fill-in for Timbo (Tim Lloyd) and was subsequently hired to present a regular Sunday evening show with a team of assistants including Nicky Keig-Shevlin, Steve Lawrence, Cathy and Mary.
At the launch of the station, Southern Sound broadcast only to Brighton and parts of West Sussex. In 1987, transmissions were extended to Lewes, Newhaven and Seaford. Then on 5 February 1989 the station won a new licence for East Sussex too. Initially running split programming for East and West Sussex, the station now only splits for commercial breaks.
In 1994 the Radio Authority merged the two licences to become one official ILR licence.
The station broadcasts to the following areas:
- Analogue VHF FM
- 96.9 MHz - Newhaven Transmitter
- 102.0 MHz - Hastings Transmitter
- 102.4 MHz - East and West Sussex, including Eastbourne (Heathfield Transmitter)
- 103.5 MHz - Brighton and Worthing (Whitehawk Hill Transmitter)
- DAB Digital Radio: Block 11B 218.64 MHz
- Heart Sussex for Crawley & Surrey broadcast to the following areas on FM:
- 102.7 MHz - Reigate Transmitter
- 97.5 MHz (around Horsham)
Network restructuring 
On 21 June 2010, Global Radio announced plans to merge Heart Sussex and merge the station with Mercury FM as part of plans to reduce the Heart network of stations from 33 to 16. The newly merged Heart Surrey and Sussex station began broadcasting from Brighton on 26 July 2010.
The merged Heart brought the addition of an additional sub-station, Heart Sussex for Crawley & Surrey operates operationally separately. Sales are dealt with by a separate team (based in Crawley) - they may be based in Brighton in the near future though. In addition, to this Heart Sussex for Crawley & Surrey also has a different website. On air though, both stations broadcast/simulcast the same core coverage with the exception of adverts (and select news features). Mercury FM and Heart have now completed the switchover and for the time being are operating out of both addresses.
Local presenters 
Networked presenters 
Head of News