Signal box prefix codes

A (hopefully) comprehensive listing

'Boxes beginning F

Last update 24 October 2025

Additional information is always gratefully received, whether entirely new records (particularly historical records) or information to fill in gaps or correct errors, via the contact link under the Miscellaneous entry in the navigation bar above. Thank you.

Please select a starting letter from the links below:

Code Signal Box Note ELRMileage Opened Closed Control to
EB Factory Junction Later code ATL6m 64ch VIR1m 61ch 25 January 1953 17 May 1980 Victoria Signalling Centre (VS)
G Believed to be earlier code
A Automatic signals
F Fairfield Junction HAJ3m 56ch by January 1907 6 May 1984 Ashburys (AS)
FJ Fairwood Junction WEY111m 16ch 1 January 1933 11 May 1984 Westbury [new] (W)
- Falmer BTL3m 44ch 23 February 1930 30 March 1985 Three Bridges [new] (T)
F Falsgrave YMS41m 63ch 1908 1 November 2010 Seamer [reopened] (YS)
FH Fareham SDP284m 10ch 1903 20 June 1982 Eastleigh [new] (E)
FJ Farington Junction CGJ5≈19m 02ch Preston (PN)
MW Farlington Junction WPH240m 38ch 1 January 1860 5 May 1968 Portsmouth (PW)
TW Farnborough BML133m 23ch 25 September 1904 20 November 1966 Basingstoke [panel] (YW)
WA Automatic signals
WZ Farncombe Named Farncombe West to 29 April 1934 WPH133m 45ch May 1897 24 October 2025 Basingstoke Rail Operating Centre (BEP)
WA Automatic signals
Farncombe West See Farncombe
FN Farnham PAA240m 40ch May 1901 27 August 2013 Woking ASC (WK)
FD Farnham Depot Shunt Panel PAA2≈41m 06ch 13 June 2005
EM Farningham Road VIR20m 26ch ≈1876 12 June 1983 Victoria Signalling Centre (VS)
A Automatic signals
FJ Farnley Junction Leeds (L)
D Down line automatic signals
U Up line automatic signals
EY Faversham VIR52m 07ch 24 May 1959 24 December 2011 East Kent Signalling Centre (EK)
A Automatic signals
Fawkham See Longfield
FN Fawkham Station VIR23m 22ch by 1873 28 November 1965 Victoria Signalling Centre (VS)
Fawley TTF91m 42ch 20 July 1925
- Faygate TBH134m 27ch 1877 20 April 1986 Three Bridges [new] (T)
F Featherstone Downgraded to gate box 17 May 1969 WAG153m 72ch 29 March 1987 Oakenshaw (O)
FF Felin Fran Downgraded to ground frame 16 June 1973: line controlled by Port Talbot (PT) SDI22m 23ch 1913 Wales Rail Operating Centre (PT) (planned)
FB Felixstowe Beach Code shown in 1970 weekly notice FED≈84m 60ch 1888 24 July 1971 Felixstowe Beach [new] (F)
F Felixstowe Beach [new] FED84m 69ch 25 July 1971 14 March 1999 Colchester [new] (CO)
NQ Felixstowe North Quay Freightliner Depot FED86m 00ch 1987
also had draw-ahead signals from 16 February 1987 labelled A-G with no number
FL Felling Unclear whether one or both codes used LEN3 15 December 1929? 17 July 1965 Gateshead (G)
F
F Feltham RDG114m 59ch 8 September 1974 2 September 2023 Basingstoke Rail Operating Centre (BEF)
BEF Shepperton branch. Code used from 24 June 2019. Temporary code until taken over by Basingstoke Signalling Control Centre (BEF)
FX Proposed code shown on plans of Staines-Heathrow 'Airtrack' extension
WBK Feltham West Downgraded to gate box 8 September 1974 RDG114m 78ch ≈1880 10 January 1975 Feltham (F)
Fence Houses See Fencehouses
F Fencehouses Also known as Fence Houses. Code used from 31 March 1987 FEP12m 43ch 1914 18 May 1991 Line closed
F Fenchurch Street FSS10m 20ch 14 April 1935 22 July 1994 Upminster IECC (UR) after temporary line closure
D Down line automatic signals
U Up line automatic signals
UF Up fast line automatic signals
US Up slow line automatic signals
Fencote Still standing 2007 BYB140m 10ch 1 September 1897 15 September 1952 Line closed
F Feniton Gate box: line controlled by Honiton (HN) BAE2159m 26ch 9 June 1974 26 March 2012 Basingstoke Signalling Control Centre (SE)
FC Fenny Compton Code used by 8 November 1953 DCL94m 76ch SJT122m 41ch 6 March 1960 1 May 2004✖last train; official closure 4 May 2004 Leamington Spa (OL)
FS Fenny Stratford BBM1m 13ch 1883 23 July 2004✖last train; official closure 6 September 2004 Marston Vale (MV)
FE Ferme Park ECM13m 55ch 1976
FP Ferme Park North Down ECM13m 68ch June 1893 7 December 1974 Wood Green (WG)
F Ferrybridge SMJ22m 10ch 1956 18 April 2006 Ferrybridge [new] (FE)
BS Code used for at least one up line signal
D Down direction automatic signals
R Distant signals
U Up direction automatic signals
FE Ferrybridge [new] SMJ22m 33ch 18 April 2006
FPS Ferrybridge Power Station JMM≈1m 60ch ? 8 April 2006
FB Unclear exactly where these signals used (or if used by Ferrybridge)
E Position light and flashing red light signals
T Unloading control signals
F Ferryhill Named Ferryhill No 2 to 28 November 1971 ECM556m 70ch December 1953 30 January 2021✖last train; official closure 10 February 2021 York Rail Operating Centre (NF)
D Down line automatic signals. Code used from 1971
RU Banner repeaters for up line automatic signals. Code used from 1971
U Up line automatic signals. Code used from 1971
Ferryhill No 2 See Ferryhill
F Ferryhill No 3 Code used from February 1966 ECM5≈56m 35ch 28 November 1971 Ferryhill (F)
D Down line automatic signals. Code used from February 1966
RU Banner repeaters for up line automatic signals. Code used from February 1966
U Up line automatic signals. Code used from February 1966 (unclear whether used at all)
FS Ferryside SWM2238m 47ch 1884 Wales Rail Operating Centre (PT) (planned)
F
FF Fiddlers Ferry Power Station Code not carried SDJ214m 46ch ≈July 1967
S Fiddlers Ferry power station control room by 1987
FE Filey HBS44m 36ch 1911 25 June 2000 Seamer [temporary panel] (SR)
Filton Incline BSW4m 14ch 8 July 1917 17 October 1970 Bristol (B)
FJ Filton Junction Code used from 19 October 1970 BSW4m 54ch 7 April 1903 20 February 1971 Bristol (B)
F Unclear if code used
DFR Down Filton relief line automatic signals. Code used from 19 October 1970
UFM Up Filton main line automatic signals. Code used from 19 October 1970
Filton West Junction AFR112m 73ch 24 April 1910 20 February 1971 Bristol (B)
F Finningley Panel fitted 4 December 1977. Downgraded to gate box 9 September 1979: line controlled by Doncaster (D) SPD4112m 07ch May 1877
FP Finsbury Park ECM1≈2m 45ch 27 April 1975 7 August 1976 Kings Cross (K)
F2 Finsbury Park No 2 ECM1≈2m 33ch 10 June 1974✖reopening date; it is unclear when originally opened or closed 13 September 1975 Finsbury Park (FP)
F3 Finsbury Park No 3 ECM12m 32ch 6 July 1911 27 April 1975 Finsbury Park (FP)
F4 Finsbury Park No 4 ECM12m 31ch 1894 20 April 1974 Finsbury Park No 6 (F6)
F5 Finsbury Park No 5 ECM12m 51ch 6 July 1911 27 April 1975 Finsbury Park (FP)
F6 Finsbury Park No 6 ECM12m 49ch 29 January 1891 8 June 1975 Finsbury Park (FP)
S6 Code reported in 1975 notice, believed in error
D Finsbury Park No 7 Down line automatic signals HBB2m 73ch 1876 8 June 1975 Line closed
U Up line automatic signals
FK Firbeck Named Firbeck A to 7 August 1983 Unclear if code carried BKS11m 20ch 1 October 1926 7 October 1984 Maltby Colliery (M)
Firbeck A See Firbeck
FB Fishbourne Crossing TBH229m 28ch 1881 23 October 1992 Chichester (CC)
DFB Distant signal (code probably not carried)
FS Fiskerton Downgraded to gate box 13 August 1994?: line controlled by Fiskerton Junction. Also known as Fiskerton Station NOB112m 42ch 6 July 1902 22 October 2016 East Midlands Control Centre (NN)
FJ Fiskerton Junction NOB112m 04ch 7 April 1929 22 October 2016 East Midlands Control Centre (NN)
FB Code reported but believed not carried
Fiskerton Station See Fiskerton
Flax Bourton MLN1124m 28ch 21 September 1958 4 December 1971 Bristol (B)
Flaxton YMS9m 21ch 11 June 1989 Strensall (S)
UW Fleet BML136m 34ch 25 September 1904 21 February 1960 Farnborough (TW)
R Distant signals
WA Automatic signals
WAR Distant to automatic signals
FL Fletton ECM174m 78ch 6 August 1890 28 April 1973 Peterborough (P)
FY Foley Crossing NSS1m 56ch 1889
R Banner repeater signals
YE Folkestone East XTD70m 79ch 18 February 1962
EBB Folkestone Harbour Last use May 2008? FFH271m 75ch 17 December 1933 29 September 2011✖date line officially taken out of use line closed
ZE Folkestone Junction Code used from 1960 XTD71m 02ch 14 November 1908 18 February 1962 Folkestone East (YE)
A Automatic signals
FB Ford Bridge SHL40m 66ch 2 October 1988 Moreton On Lugg (ML)
FR Forders Sidings Believed code not carried BBM11m 74ch 1930 23 July 2004✖last train; official closure 6 September 2004 Marston Vale (MV)
CBW Ford Junction TBH219m 31ch 10 March 1912 8 December 1979 Arundel (AR)
F Forest Gate Later code LTN15m 63ch 1895 24 August 1996 Liverpool Street [new] (L)
FG Earlier code
DE Down electric line automatic signals
DM Down main line automatic signals
RF Repeater signals
UE Up electric line automatic signals
UM Up main line automatic signals
FH Forest Hall Downgraded to gate box 1940 ECM7≈4m 77ch 6 February 1965 Benton (B)
LC Forest Hill LBW5m 75ch 8 October 1950 15 June 1969 Norwood Junction (JC)
CA Automatic signals
JC Temporary code for 14 June 1969 only, until taken over by Norwood Junction
FJ Fork Junction Location not certain LLS20m 10ch 1881 ≈19 March 1973 Stratford (S)
F Forres Named Forres East to 1967 Code used from 2002 to 2003 ANI20m 17ch 20 October 1896 7 October 2017 Inverness (HE)
FS Code from 11 January 2002
Forres East See Forres
F Forth Believed code used from 12 April 1959 NEN10m 55ch 31 May 1908 6 February 1966 Newcastle (N)
FW Fort William Junction Named Mallaig Junction to 27 March 1988 Code used from renaming MLG10m 05ch WHL98m 65ch 6 August 1894
FD Fouldubs Junction GMH1m 51ch 12 January 1908
FO Four Oaks ALC16m 21ch 12 October 1992 Aston (AN)
FD Foxfield Believed code not carried CBC140m 40ch 1879
F Foxton Downgraded to gate box 26 February 1983: line controlled by Cambridge (CA). Unclear whether code carried SBR50m 73ch 20 August 1878
FR Fratton A Stop boards WPH243m 70ch 1968
GF Ground frame controlled signals
F Freemans Code used by 1974 WSB1m 31ch 1956
FE Freightliner Depot East End Ground Switch Panel TLL≈10m 00ch 27 May 1996
FW Freightliner Depot West End Ground Switch Panel TLL9m 50ch 27 May 1996
FT Freight Terminal Ground Frame [Kings Cross] Upgraded to signal box ≈1987 CRF3 29 September 1975 10 June 1989 Kings Cross (K)
FD Freshfield Downgraded to gate box HXS317m 78ch 1878 1 May 1994 Merseyrail (ML)
Friargate MAC3109m 03ch 1884 12 April 1990✖burnt out; official closure September 1993 Pasture Street (P)
FJ Friars Junction MLN13m 53ch 9 March 1902 8 October 1962 Old Oak Common (OO)
UW Frimley Junction Code used from 1963 AAV9m 61ch June 1879 25 March 1973 Ash Vale Junction (HW)
F Frinton Gate box: line controlled by Thorpe-le-Soken (T) TWN68m 76ch ≈1924 4 May 2009 Colchester [new] (CO)
FY Frisby GSM3110m 17ch 23 February 1941
Frodingham Trent Junction See Trent Junction
FJ Frodsham Junction FJH1m 49ch 1912
F Fryston NOC18m 03ch 25 April 1987 Castleford (C)
FN Normanton line signals
F Fulbourne CCH4m 34ch 1875 7 May 1983 Cambridge (CA)
FV Furness Vale BEJ8m 57ch 1887