Here is a list of FM stations available in Southborough on 13th July 2022.
Included are French stations that are audible occasionally due to unusual atmospheric conditions – the 400kW transmitters at Lille in NE France can be very strong at these times.
On 30th December 2019, various Belgian radio stations were audible in Southborough for one day only (again due to unusual atmospherical conditions) and these are added in italics.
A separate list of DAB and DAB+ stations can be found on this link:
https://southborough-news.com/dab-radio/
CR = Low Power Community Radio station
* = Audible only under certain conditions
Iow = from Isle of Wight
88.0 88.1 R2 Guildford 88.2 88.3 Vacant 88.4 88.5 R2 Rowridge, IoW 88.6 88.7 France Musique, Lille* 88.8 R2 Crystal Palace 88.9 89.0 89.1 R2 Wrotham 89.2 89.3 89.4 France Musique, Boulogne 89.5 Klara, Brussels* 89.6 89.7 R2 Norfolk 89.8 88.9 90.0 R2 Dover 90.1 90.2 90.3 R3 Guildford 90.4 Klara, Flanders* 90.5 90.6 90.7 R3 Rowridge, IoW 90.8 90.9 91.0 R3 Crystal Palace 91.1 91.2 91.3 R3 Wrotham 91.4 91.5 91.6 91.7 91.8 91.9 R3 Norfolk 92.0 92.1 Vacant 92.2 CR: Sheerness, Io Sheppey 92.3 92.4 R3 Dover 92.5 R4 Guildford 92.6 92.7 French Rap, Boulogne 92.8 92.9 R4 Rowridge, IoW 93.0 93.1 93.2 R4 Crystal Palace 93.3 RIRE&, Boulogne* 93.4 93.5 R4 Wrotham 93.6 93.7 93.8 93.9 94.0 94.1 R4 Norfolk 94.2 94.3 94.4 R4 Dover 94.5 94.6 94.7 CR: Ashdown, Crowborough 94.8 94.9 BBC R London (4kW) 95.0 95.1 95.2 95.3 BBC Essex, Southend 95.4 95.5 CR: West Kent, Bidborough 95.6 95.7 R1 Belgium Egem* 95.8 Capital Croydon (4kW) 95.9 96.0 96.1 96.2 KMFM Pembury 96.3 96.4 Greatest Hits, Guildford 96.5 96.6 96.7 BBC R Kent Wrotham 96.8 96.9 97.0 97.1 97.2 97.3 LBC Croydon (4kW) 97.4 97.5 Heart Horsham 97.6 97.7 R1 Guildford 97.8 CR: Basildon/Croydon 97.9 98.0 France Culture, Lille* 98.1 98.2 R1 Rowridge, IoW 98.3 98.4 98.5 R1 Crystal Palace 98.6 R2 Belgium, E Egem* 98.7 98.8 R1 Wrotham 98.9 99.0 99.1 99.2 99.3 R1 Norfolk 99.4 99.5 R1 Dover 99.6 99.7 Vacant 99.8 99.9 France Culture, Boulogne 100.0 Kiss, Croydon (2kW) 100.1 R2 Belgium W Egem* 100.2 Dream 100 Essex 100.3 100.4 KMFM Gillingham 100.5 100.6 Classic FM, C Palace 100.7 100.8 100.9 Classic FM Wrotham 101.0 101.1 101.2 101.3 101.4 101.5 101.6 KMFM Wrotham 101.7 101.8 Classic FM Dover 101.9 102.0 102.1 Studio Brussels* 102.2 Smooth Croydon (2kW) 102.3 102.4 Heart Heathfield 102.5 102.6 102.7 Heart Reigate 102.8 102.9 103.0 103.1 Heart Maidstone 103.2 103.3 France Inter, Boulogne 103.4 103.5 BBC Essex, North 103.6 103.7 France Inter, Lille* 103.8 103.9 Europe 1, Boulogne 104.0 BBC Surrey, Reigate 104.1 104.2 BBC Kent, Dover 104.3 104.4 104.5 BBC Sussex Heathfield 104.6 104.7 104.8 104.9 Radio X, C Palace (3kW) 105.0 105.1 Radio Essex, Southend 105.2 France Info, Lille* 105.3 105.4 Magic Croydon (4kW) 105.5 105.6 KMFM Maidstone 105.7 105.8 Gt Hits C Palace (4kW) 105.9 106.0 KMFM Canterbury 106.1 106.2 Heart Croydon (4kW) 106.3 106.4 More Radio, Haywards Heath 106.5 France Info, Boulogne 106.6 106.7 CR: West Kent, Tun Wells 106.8 More Radio, Lewes 106.9 107.0 CR: East Grinstead 107.1 Capital Xtra, Alexandra Palace 107.2 107.3 Vacant 107.4 107.5 Time East London 107.6 KMFM Ashford 107.7 Radio Essex, Chelmsford 107.8 107.9 KMFM Hoo/Medway |
The following map is a Photoshop montage I’ve done of the service areas of the BBC FM Transmitter network for SE England. It illustrates why so much of the FM network is needed for the four FM National Radio services.

Transmitters that have overlapping reception areas need 3 or 4 MHz frequency spacing. Most car radios retune automatically from one Radio 4 FM transmitter to the next, but all general home portable radios require manual retuning if you move or go on holiday. For the frequencies to type in or tune to click here:
http://www.frequencyfinder.org.uk/