Signal box prefix codes

A (hopefully) comprehensive listing

Non-national rail codes

Last update 2 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:

Croydon Tramlink signals

Croydon Tramlink signal codes can be found on the Croydon Tramlink Unofficial Site.

Docklands Light Railway signals

Although the Docklands Light Railway is an automated system, trains are driven manually in the depots. At present, only five signal codes are known, all for Poplar depot. These are AS, AT, DA, DB and WA.

Edinburgh Tramway signals

It appears that the only labelled signals are in the depot area or are points indicators with codes based on the nearby station. In addition, road traffic crossings are labelled sequentially from ET1. Prefixes known at present are:

Code Area
AIR Airport
BAL Balfour Street shown on pre-opening training video
BFS Balfour Street present on site
DEP Depot
HAY Haymarket
NEW Newhaven
OCT Ocean Terminal
ODR Ocean Drive
PIL Pilrig Street
PPL Picardy Place
SHO The Shore
SHP Shandwick Place
TOW Top of the Walk
VIC Victoria Swing Bridge
YPL York Place

'Stop' signals are labelled in the form DEP R1 04, points indicators in the form HAY PPI 02.

Glasgow Subway signals

Most signals appear not to carry a prefix. Those seen with a prefix carry A.

London Underground signals

Main codes

London Underground (and its predecessors) has a complex signal labelling system. A summary can be found below. Note that the Underground is not my particular speciality: most of the raw data coming from District Dave's site (Page 1, Page 2, Page 3 broken links), and from Tube Prune (these sources are not identical), in addition to other observations. In addition to these codes, a 1930s photograph shows signals at Stanmore (controlled from Wembley) displaying Y8LA and Y4LA on the same post. The Y represents Stanmore area control, and the L signifies 'push-pull lever control'. The smaller A denotes platform 1; platform 2 had equivalent numbers with a 'B'.

Code Control centre or relay room Current Line (for numbering series purposes) Date code used (where known) Became or taken over by (where known)
BMX 'Special' signal Bakerloo -
A Automatic signals general use -
S Automatic signals Northern All gone by 2014 -
X Last automatic signal before controlled area (also used in combination with controlled area code) general use -
R Repeater signals used on all lines -
FDX Floodgate signals at Embankment and South Kensington District 1939- -
FNX Floodgate signals at Bank, Charing Cross, London Bridge and Waterloo Northern 1939-2014 -
FNX Floodgate (?) signals at Kennington, Moorgate and Tottenham Court Road Northern 1958-2014 -
FX Floodgate signals at Green Park and Oxford Circus Victoria 1968-2012 VGPF
CAT Canning Town Jubilee 2010- -
TN Canning Town Jubilee 1999-2010 CAT
X Floodgate signals Bakerloo 1990- -
FBX Floodgate signals at Embankment and Waterloo Bakerloo 1939-1990 X
PNX Possession protection signals used on all lines -
WL Acton Town District 1905- -
E Aldersgate (Barbican) Metropolitan, Circle 1865-1954 OG
P Aldersgate (Widened Lines) Metropolitan, Circle 19xx-1924 E
H Aldgate Metropolitan, Circle 1909-1946 OB
OB Aldgate and Aldgate East Circle 1946- -
EL Aldgate East District 1906-1946 OB
JW Amersham Metropolitan 1960- -
K Angel Northern 1919-1959 -
ARC Archway Northern 2013- -
J Arnos Grove Piccadilly 1932-1982 PJ
PJ Arnos Grove Piccadilly 1982- -
BAS Baker Street Jubilee ? -
BM Baker Street Jubilee 1939-? BAS
MB Baker Street Metropolitan 1947- -
MBX Baker Street intermediate stop signals (indicates an X signal) Metropolitan 1947- -
RMB Repeater for Baker Street signals Metropolitan 1947- -
M Baker Street Metropolitan, Circle 1928-1947 MB
A Baker Street (also recorded as B in some sources) Metropolitan, Circle 1913-1928 M
B See Baker Street (A)
B Bank Central 1914-1941 CB
BAN Bank Central 1996- -
CB Bank Central 1941-1971 -
OG Barbican Circle 1954-1979 -
FF Barking & Upney District 1960- -
FFX Barking & Upney intermediate stop signals (indicates an X signal) District 1960- -
RFF Repeater for Barking & Upney signals District 1960- -
RFFX Repeater for Barking & Upney intermediate stop signals (?) District 1960- -
BAR Barkingside Central 1996- -
LN Barkingside Ground Frame Central 1948-1965 -
WC Barons Court District 1962-1983 -
WD Barons Court District 1906- -
X Barons Court surface stock detector District ?? -
BER Bermondsey Jubilee 2010- -
TR Bermondsey Jubilee 1999-2010 BER
BEG Bethnal Green Central 1995- -
LC Bethnal Green Central 1946-1995 -
VBR Blackhorse Road Victoria 2010- -
LY Blake Hall Ground Frame (no signals present) Central 1957-1967 -
BOS Bond Street Jubilee 2010- -
X Borough Northern 1922-1923 -
WS Boston Manor District 1974- -
EP Bow Road District 1907-1964 -
AA Brent Cross Northern 1926-1937 -
C British Museum Central 1900-1933 CB
VE Brixton Victoria 1971-2010 VBN
VBN Brixton Victoria 2010- -
FB Bromley-By-Bow District 1960- -
FBX Bromley-By-Bow advanced starting board District 1960- -
FRFB Fog repeater for Bromley-By-Bow signals (similar for other fog repeaters, not all are known and shown here) District 1960- -
FRFBX Fog repeater for Bromley-By-Bow intermediate stop signals District 1960- -
RFB Repeater for Bromley-By-Bow advanced signals District 1960- -
RFBX Repeater for Bromley-By-Bow advanced starting board District 1960- -
BUH Buckhurst Hill Central 1996- -
LS Buckhurst Hill Ground Frame Central 1948-1965 -
BT Camberwell Green (planned, not used) Bakerloo - -
E Camden Town Northern 1907-2013 CTN
CTN Camden Town Northern 2013- -
CDW Canada Water Jubilee 2010- -
TK Canada Water Jubilee 1999-2010 CDW
E Canal Junction East London 1913-1950 ET
ET Canal Junction East London 1950-1997 -
ETX Canal Junction advance starting signals East London 1950-1997 -
FRETX Canal Junction advance starting signal fog repeater East London 1950-1997 -
RET Canal Junction intermediate stop repeater signals East London 1950-1997 -
RF Canal Junction Proposed Fleet Line/East London - -
CRW Canary Wharf Jubilee 2010- -
TL Canary Wharf Jubilee 1999-2010 CRW
MJ Canons Park Metropolitan 1941-1971 -
WW Canons Park Metropolitan 1941-1941 MJ
CAP Canons Park Jubilee 2011- -
JT Chalfont Metropolitan 1949-1959, 1960- JW
JW Chalfont Metropolitan 1959-1960 JT
CHL Chancery Lane Central 1996- -
CHX Charing Cross Jubilee 2010- -
TG Charing Cross Jubilee 1978-2010 CHX
C Charing Cross Northern 1937-2013 CHX
RC Charing Cross Proposed Fleet Line/East London - -
CHX Charing Cross Northern 2013- -
JV Chesham Metropolitan 1949-1970 -
CHI Chigwell Central 1996- -
JS Chorleywood Metropolitan 1954-1970 -
T Clapham Common Northern 1919-1976 -
M Cockfosters Piccadilly 1933-1982 PM
PM Cockfosters Piccadilly 1982- -
AC Colindale Northern 1924-2013 CDL
CDL Colindale Northern 2013- -
B Covent Garden Piccadilly 1906-1931 C
C Covent Garden Piccadilly 1931-1979 -
FPX Green Park/Russell Square 'special' signals (exact meaning uncertain) Piccadilly 1958- -
EC Cromwell Road District 1906-1967 -
B Croxley Metropolitan 1924-1970 -
FG Dagenham East District 1960- -
DEB Debden Central 1996- -
LU Debden Central 1949-1996 DEB
D Deptford Road Junction (GF emergency crosover) East London 1913-1950 -
MX Dollis Hill Metropolitan 1938-1939 -
DOH Dollis Hill Jubilee ? -
PB Down Street Piccadilly 1979- -
LD Drapers Field (Leyton) (temporary reversing siding) Central 1946-1947 -
B Drayton Park Northern City 1904-1953 NC
NC Drayton Park and Finsbury Park Northern City 1939-1976 -
EAB Ealing Broadway Central 1993- -
L Ealing Broadway Central 1920-1952 WP
WP Ealing Broadway District 1905- -
WM Ealing Common District 1905- -
WMX Ealing Common depot District ?? -
EC Earls Court (Main) District 1966- -
EA Earls Court East District 1905-1936 EC
WA Earls Court West District 1905-1966 EC
LMR Distant signal for Earls Court junction Code not carried: used on signalling plan to denote London Midland Region (BR) signal box control
EAA East Acton Central 1996- -
MS Eastcote (also recorded as MR in some sources) Metropolitan 1948-1966 -
MR See Eastcote (MS)
T Eastcote (also recorded as R in some sources) Metropolitan 1930-1948 MS
R See Eastcote (T)
NP East Finchley Northern 1939-1961 -
FRNP Fog repeater for East Finchley signals Northern 1939-1961 -
EFN East Finchley Northern 2013- -
FE East Ham District 1960- -
FEX East Ham last automatic signal before controlled area District 1960-1995 -
RFE Repeater for East Ham signals District 1960- -
FD East Ham (planned, not used) District - -
AE Edgware Northern 1924-2013 EDG
EDG Edgware Northern 2013- -
A Edgware Road Bakerloo 1907-1913 -
B Edgware Road Metropolitan, Circle 1907-1951 OP
OP Edgware Road Metropolitan, Circle 1951- -
ROPX Repeater for Edgware Road intermediate stop signals Metropolitan, Circle 1951- -
BS Elephant & Castle Bakerloo 1941-1991 -
E Elephant & Castle Bakerloo 1906-1941 BS
Q Elephant & Castle Northern -
EH Embankment District 1905- -
EPP Epping Central 1996- -
LW Epping Central 1949-1996 -
J Euston Northern 1919-2013 EUS
EUS Euston Northern 2013- -
VEU Euston Victoria 2010- -
OZ Euston Square Metropolitan, Circle 1941-19xx -
FAI Fairlop Central 1996- -
LM Fairlop Ground Frame Central 1948-1964 -
FRLM Fairlop fog repeater Central 1948-1997 -
A Fairlop automatic signals Central 1948-1997 -
FR Fairlop automatic signals fog repeaters Central 1948-1997 -
D Farringdon Metropolitan, Circle 1909-1956 OH
OH Farringdon Metropolitan, Circle 1956- -
M Farringdon (Widened Lines) Metropolitan, Circle 19xx-1924 D
RD Fenchurch Street Proposed Fleet Line/East London - -
NQ Finchley Central Northern 1940-1969 -
NQX Finchley Central advance starting board Northern 1940-1969 -
RNQ Repeater for Finchley Central signals Northern 1940-2013 -
FRNQ Fog repeater for Finchley Central signals Northern 1940-1969 -
FNC Finchley Central Northern 2013- -
FIR Finchley Road Jubilee 2010- -
JD Finchley Road Jubilee 1984-2010 FIR
MD Finchley Road Metropolitan 1937- -
C Finchley Road (also recorded as D) Metropolitan 1911-1937 MD
D See Finchley Road (C)
C Finsbury Park Northern City 1904-1939 NC
F Finsbury Park Piccadilly 1906-1965 VK
VK Finsbury Park Victoria 1968-2010 VFP
VKX Temporary Finsbury Park signals whilst rebuilding to divert Piccadilly line Victoria 1968 VFP
VFP Finsbury Park Victoria 2010- -
GAH Gants Hill Central 1996- -
EE Gloucester Road/South Kensington District 1906-1957 EC
K Gloucester Road Metropolitan, Circle 1909-1952 OQ
OQ Gloucester Road Metropolitan, Circle 1952-1957 EC
G Golders Green Northern 1907-2013 GGN
GGN Golders Green Northern 2013- -
GRH Grange Hill Central 1997- -
LK Grange Hill (subsiduary to Hainault) (code never allocated though provision made), also recorded as LL Central 1948-1997 GRH
B Great Central (Marylebone) Bakerloo 1907-1915 -
GRP Green Park Jubilee 2010- -
TF Green Park Jubilee 1999-2010 GRP
VGP Green Park Victoria 2010- -
VGPF Green Park/Oxford Circus floodgate signals Victoria 2012- -
CL Greenford Central 1947-1960 -
CLX Greenford Central 1947-1948 -
GRE Greenford Central 1996- -
HAI Hainault Central 1997- -
LL Hainault/Grange Hill Central 1948-1997 -
LLX Hainault/Grange Hill advance starting signals (?) Central 1948-1997 -
FRLX Hainault/Grange Hill fog repeater Central 1948-1997 -
H Hammersmith Hammersmith & City 1921-1951 OZ
OZ Hammersmith Hammersmith & City 1951- -
A Hammersmith Piccadilly 19xx-1932 WD
F Hampstead Northern 1907-2013 HMP
HMP Hampstead Northern 2013- -
HAL Hangar Lane Central 1996- -
WO Hanger Lane Junction (also recorded as WN) District 1905-1925 WM
WN See Hanger Lane Junction (WO)
N Harrow North Metropolitan 1908-1948 JB
H Harrow South Metropolitan 1908-1948 JB
J Harrow Station Metropolitan 1908-1948 JB
JB Harrow-on-the-Hill Metropolitan 1948- -
WW Hatton Cross Piccadilly 1975- -
WY Heathrow Central Piccadilly 1977- -
AB Hendon Central Northern 1923-1930 -
NU High Barnet Northern 1940-2013 HBT
HBT High Barnet Northern 2013- -
VJ Highbury Victoria 1968-2010 VHY
VHY Highbury & Islington Victoria 2010- -
H Highgate (Archway) Northern 1907-1939 NN
NN Highgate (Archway) Northern 1939-2013 ARC
NH Highgate Depot Panel Northern 1989- -
EB High Street Kensington District 1907-1936 -
ED High Street Kensington District 1967- -
J High Street Kensington Metropolitan 1909-1926 EB
MV Hillingdon Metropolitan 1948-1966 -
V Hillingdon Metropolitan 1930-1948 MV
C Holborn Central 1933-1941 CC
CC Holborn Central 1941-1994 HOL
HOL Holborn Central 1994- -
D Holborn/Aldwych Piccadilly 1906-1980 PD
PD Holborn/Aldwych Piccadilly 1980- -
HOP Holland Park Central 1996- -
FJ Hornchurch District 1959- -
FK Hornchurch (code was never used) District - FJ
WT Hounslow Central District 1910- -
X Hounslow Central surface stock detector District ?? -
WS Hounslow East/Town District 1905-1923 -
WX Hounslow West District 1926-1975 -
WT Hounslow West/Barracks District 19xx-≈1905 -
A Hyde Park Corner Piccadilly 1906-1931 B
B Hyde Park Corner Piccadilly 1931-1979 PB
WH Junction with LWSR at Ravenscourt Park suspected but not confirmed District -
A Kennington Northern 1926-1937 B
B Kennington Northern 1937-2013 KEN
Y Kennington (temporary control) Northern 1923-19xx -
KEN Kennington Northern 2013- -
D Kennington Road (Lambeth North) Bakerloo 1906-1939 BR
KIL Kilburn Jubilee 2010- -
KIN Kingsbury Jubilee 2011- -
OJ Kings Cross Metropolitan 1941- -
OJX
C Kings Cross Metropolitan, Circle 1908-1958 OJ
J Kings Cross Metropolitan, Circle 1912-1939 -
L Kings Cross Northern 1927-1956 -
VH Kings Cross Victoria 1968-2010 VKC
VKC Kings Cross St Pancras Victoria 2010- -
E Ladbroke Grove Hammersmith & City 1921-1950 OU
OU Ladbroke Grove Hammersmith & City 1950-1983 -
BR Lambeth North Bakerloo 1939-1991 -
LAG Lancaster Gate Central 1996- -
F Latimer Road Hammersmith & City 1921-1950 OV
OV Latimer Road Hammersmith & City 1950-1957 -
RK Lewisham Proposed Fleet Line/East London 1973 -
LE Leyton Central 1947-1971 -
LEY Leyton Central 1996- -
LES Leytonstone Central 1997- -
LF Leytonstone Central 1947-1997 -
LFX Leytonstone Central 1947-1997 -
A Liverpool Street Central 1912-1937 LB
LB Liverpool Street Central 1937-1997 LIS
FCX Tottenham Court Road/Liverpool Street 'special' signals exact meaning uncertain Central 1958-1999 -
LIS Liverpool Street Central 1997- -
G Liverpool Street Circle 1910-1954 OD
OD Liverpool Street Circle 1954- -
LOB London Bridge Jubilee 2010- -
TJ London Bridge Jubilee 1999-2010 LOB
P London Bridge Northern 1919-2014 -
D London Road Depot Bakerloo 1906-1915 D
B Lords Metropolitan 1910-1937 MC
MC Lords Metropolitan 1937-1971 ML
LOU Loughton Central 1997- -
LT Loughton Central 1948-1997 -
EG Mansion House District 1973- -
EI Mansion House District 1928-1973 EG
CD Marble Arch Central 1941-1994 MAA
D Marble Arch Central 1914-1941 CD
MAA Marble Arch Central 1994- -
MIE Mile End Central 1996- -
NV Mill Hill East Ground Frame Northern 1943-1964 -
EK Minories Junction District 1906-1909 EL
D Moor Park Metropolitan 1924-1953 -
JG Pinner Metropolitan 1962-1971 -
OE Moorgate Circle 1956- -
F Moorgate Metropolitan, Circle 1909-1956 OE
M Moorgate Northern 1919-2013 MGT
MGT Moorgate Northern 2013- -
A Moorgate Northern City 1904-1922 D
D Moorgate Northern City 1922-1937 ND
ND Moorgate Northern City 1937-1976 -
R Moorgate (Widened Lines) Metropolitan, Circle 19xx-1926 F
Y Morden Northern 1926-2013 MOR
MOR Morden Northern 2013- -
Z Morden Depot Ground Frame (unofficial code) Northern 1926- -
D Mornington Crescent Northern 1907-1924 E
JM Neasden Jubilee 1985-2011 NEA
NEA Neasden Jubilee 2011- -
F Neasden Metropolitan 1911-1938 MF
MM Neasden Metropolitan 1985- -
JF Neasden (code never used) Jubilee 1985- -
MH Neasden North Metropolitan 1939-1987 -
MF Neasden South Metropolitan 1938-1987 MM
RJ New Cross Proposed Fleet Line/East London - -
RH New Cross Gate Proposed Fleet Line/East London - -
LP Newbury Park Central 1947-1994 NEP
NEP Newbury Park Central 1994- -
CJ North Acton Central 1947-1996 NOA
K North Acton Central 1920-1947 CJ
NOA North Acton Central 1996- -
WU North Ealing District 1907-1971 -
NOG North Greenwich Jubilee 2010- -
TM North Greenwich Jubilee 1999-2010 NOG
LX North Weald Central 1957-1978 -
WR Northfields District 1916- -
CP Northolt Central 1960-1996 -
NOR Northolt Central 1996- -
VN Northumberland Park Victoria 1968-2010 -
VNP Northumberland Park Victoria 2010- -
E Northwood Metropolitan 1924-1962 JF
JF Northwood Metropolitan 1962-1962 -
F Northwood Hills Siding Ground Frame Metropolitan 1924-1953 -
JE Northwood Hills Temporary Box Metropolitan 1961-1962 -
NHG Notting Hill Gate Central 1996- -
K Oakwood Piccadilly 1933-1982 PK
PK Oakwood Piccadilly 1982- -
L Old Street Northern City 1919-1922 -
LZ Ongar Central 1957-1969 LX
WR Osterley Park District 19xx-1910 -
OXC Oxford Circus Central 1996- -
VOC Oxford Circus Victoria 2010- -
BD Paddington Bakerloo 1939- -
C Paddington Bakerloo 1913-1939 BD
OR Paddington Suburban (some doubt whether code used) Circle -
NH Park Junction Northern 1939-1984 -
WF Parsons Green District 1905- -
PER Perivale Central 1996- -
B Piccadilly Circus Bakerloo 1915-1939 BP
BP Piccadilly Circus Bakerloo 1939- -
BPZ Piccadilly Circus station starting signals (controlled from Bakerloo cabin) Piccadilly 1939-1980 -
BZ Piccadilly Circus station starting signals (controlled from Bakerloo cabin) Piccadilly 1934-1939 BPZ
Y Piccadilly Circus station starting signals (controlled from Bakerloo cabin) Piccadilly 1915-1927 -
VPM Pimlico Victoria 2010- -
G Pinner Metropolitan 1924-1962 JD
JD Pinner Metropolitan 1962-1970 -
FC Plaistow District 1959-7 May 1960 (?) -
FCX Plaistow last automatic signal before controlled area District 1959- -
RFC Repeater for Plaistow signals District 1959- -
A Praed Street Junction Metropolitan, Circle 1908-1926 B
MZ Preston Road Metropolitan 1938-1948 -
WG Putney Bridge District 1905- -
QUE Queensbury Jubilee 2011- -
A Queens Park Bakerloo 1915-1937 BB
BB Queens Park Bakerloo 1937- -
CE Queens Road (Queensway) Central 1941-1984 -
E Queens Road (Queensway) Central 1914-1941 CE
QUE Queensway Central 1996- -
MP Rayners Lane Metropolitan 1985- -
P Rayners Lane Metropolitan 1925-1985 MP
REB Redbridge Central 1996- -
JP Rickmansworth Metropolitan 1953- -
K Rickmansworth Metropolitan 1910 or 1924-1953 JP
ROV Roding Valley Central 1996- -
RE Rotherhithe/Surrey Docks Proposed Fleet Line/East London - -
TRX Track replacement signal for Royal Oak (westbound) Hammersmith & City -
X Royal Oak (special signals activated by derailment detector in main line goods yard) Hammersmith & City 1970-1978 -
MT Ruislip Metropolitan 1948-1975 -
U Ruislip Metropolitan 1930-1948 MT
RUG Ruislip Gardens Central 1993- -
MU Ruislip Siding Metropolitan 1975- -
EG St James's Park District 1905-1967 -
SJW St Johns Wood Jubilee 2010- -
EM St Marys Junction (planned, not used) District - -
STP St Paul's Central 1996- -
VL Seven Sisters Victoria 1968-2010 -
VSS Seven Sisters Victoria 2010- -
F Shepherd's Bush Central 1914-1938 -
SHB Shepherd's Bush Central 1996- -
A Shoreditch East London 1913-1928 -
B Shoreditch/Whitechapel East London 1943-1995, 1998- -
N Smithfield (Widened Lines) Metropolitan, Circle 1909-1918 PK
SNA Snaresbrook Central 1996- -
LG Snaresbrook Ground Frame Central 1947-≈1954 -
WQ South Acton District 1905-1932 -
WV South Harrow District 1932- -
EF South Kensington District 1967- -
L South Kensington Metropolitan 1909-1949 OR
OR South Kensington Metropolitan 1949-1957 EC
SOR South Ruislip Central 1996- -
LH South Woodford Central 1947-1972 -
SOW South Woodford Central 1996- -
SOU Southwark Jubilee 2010- -
TP Southwark Jubilee 1999-2010 SOU
JL Stanmore Jubilee 1984-2011 STA
MK Stanmore Bakerloo 1938-1984 JL
Y Stanmore (controlled from Wembley Park CTC) Metropolitan 1932-1938 -
STA Stanmore Jubilee 2011- -
U Stockwell Northern 1919-1962, 1976-2013 SKW
SKW Stockwell Northern 2013- -
VST Stockwell Victoria 2010- -
B Strand Northern 1907-1937 C
C Strand/Charing Cross Northern 1937- -
STM Stratford Market depot entrance/exit Jubilee 2010- -
STR Stratford Jubilee 2010- -
TW Stratford Jubilee 1999-2010 STM/STR
LD Drapers Field (near Leyton) Central -
TY Stratford Market Depot Jubilee 1999- -
WW Sudbury Hill District 1933-1966 -
C Surrey Docks East London 1913-1950 ER
FECX 'Special' signals (exact meaning uncertain) East London -1995 -
ER Surrey Docks/Quays District 1950- -
ML Swiss Cottage Metropolitan 1964- -
SWC Swiss Cottage Jubilee 2010 -
THB Theydon Bois Central 1996- -
LV Theydon Bois Ground Frame Central 1949-1967 -
W Tooting Broadway Northern 1926-2013 TBY
TBY Tooting Broadway Northern 2013- -
TCR Tottenham Court Road Central 1996- -
VTH Tottenham Hale Victoria 2010- -
NT Totteridge Ground Frame Northern 1940-2013 -
EJ Tower Hill District 1967- -
WK Turnham Green District 1911- -
FM Upminster District 1958- -
MW Uxbridge Metropolitan 1938- -
W Uxbridge Metropolitan 1930-1938 MW
VVH Vauxhall Victoria 2010- -
VF Victoria Victoria 1969-2010 VVC
VVC Victoria Victoria 2010- -
VP Walthamstow Central Victoria 1968-2010 VWC
VWC Walthamstow Central Victoria 2010- -
WAN Wanstead Central 1996- -
VG Warren Street Victoria 1968-2010 VWS
VWS Warren Street Victoria 2010- -
BR Lambeth North Bakerloo 1991- -
BS Elephant & Castle Bakerloo 1991- -
TH Waterloo Jubilee 1999-2010 WAT
WAT Waterloo Jubilee 2010- -
A Watford Metropolitan 1924-1948 JL
JL Watford Metropolitan 1948-1958 JP
C Watford Junction (Croxleyhall) Metropolitan 1924-1955 JP
JJ Watford South Junction (Croxleyhall) Metropolitan 1962- -
JG Wembley Park Jubilee 1984-2011 WEP
G Wembley Park Metropolitan 1911-1937 MG
MG Wembley Park Metropolitan 1937- -
WEP Wembley Park Jubilee 2011 -
WEA West Acton Central 1996- -
D Westbourne Park Hammersmith & City 1921-1950 OS
OS Westbourne Park Hammersmith & City 1950-1971 -
ROS Repeater signal for Westbourne Park Hammersmith & City 1950-1971 -
TRX Track replacement signal for Westbourne Park (eastbound) Hammersmith & City -
WE West Brompton District 1906-1971 -
TU West Ham/Stratford (West end) Jubilee 1999-2010 WEH
WEH West Ham Jubilee 1996-2010 -
D West Hampstead Metropolitan 1911-1937 MD
JD West Hampstead Jubilee 1984-2010 WHD
WHD West Hampstead Jubilee 2010- -
WB West Kensington East and Olympia District 1906- -
FRWB Fog repeater for West Kensington East and Olympia District 1906- -
WC West Kensington West District 1906- -
WES Westminster Jubilee 2010- -
WER West Ruislip Central 1991- -
CS West Ruislip/Ruislip Gardens Central 1948-1991 WER
CGX White City temporary system until main signal cabin opened Central 1947-1948 CG
CG White City Central 1948-2000 WHC
WHC White City Central 1996- -
EN Whitechapel District 1907- -
B Whitechapel East London 1913- EN
Q Whitecross Street (Widened Lines) Metropolitan, Circle 19xx-1916 P
E Willesden Green Metropolitan 1911-1938 ME
JE Willesden Green Jubilee 1984-2010 -
ME Willesden Green Metropolitan 1937-1985 JE (in part)
WIG Willesden Green Jubilee 2010- -
WOO Woodford Central 1997- -
LJ Woodford Central 1947-2000 WOO
G Wood Green Piccadilly 1932-1980 PG
PG Wood Green Piccadilly 1980- -
G Wood Lane Central 1914-1948 CG
J Wood Lane Junction Central 1920-1938 -
NS Woodside Park Ground Frame Northern 1940-1965 -
E York Road Piccadilly 1906-1964 -

Alternative listing

Amongst a listing of station codes, London Transport gives these three-letter codes as 'Victoria Line signalling codes'. They are very different to the Victoria Line codes above.

Code Station
BLR Blackhorse Road
BRI Brixton
EUS Euston
FIP Finsbury Park
GRP Green Park
HII Highbury & Islington
KCS King's Cross St. Pancras
OXC Oxford Circus
PIM Pimlico
SES Seven Sisters
STO Stockwell
TOH Tottenham Hale
VAU Vauxhall
VIC Victoria
WAC Walthamstow Central
WAS Warren Street

Luas signals

The only prefix noted (2019) are points indicators on Line B that, logically, carry B. It is thus possible that Line A points indicators carry A.

Manchester Metrolink signals

Originally, on the bulk of the network stop signals did not carry a prefix. Repeater signals carried R. Between Altrincham and Timperley was controlled by the national network signal box at Deansgate Junction with DJ signals in the 500 series. For the remainder of the system, a Network Rail signalling plan uses QR (Queens Road).

The system has received a new control system which has introduced new signal codes. These have a prefix based on the nearby station, and suffix S (stop signals) or P (points indicators). Prefixes known at present are:

Code Area
AIR Manchester Airport
ASH Ashton-Under-Lyne
BDW Broadway
BRY Bury
CBK Cornbrook Reported in error? See CNK, seen on site
CNK Cornbrook
CPR Crumpsall
DCF Deansgate-Castlefield
DYL Droylsden
ECC Eccles
EDD East Didsbury
EXS Exchange Square
FIR Firsbrook
HBC Harbour City
HGS Hagside
IRK Irk Valley Junction
IWM Imperial War Museum
MEC MediaCityUK
MKT Market Street
MON Monsall
NEB Newbold
NHM Newton Heath & Moston
NIS New Islington
OLD Old Trafford
PIC Piccadilly
POM Pomona
QNS Queens Road including depot
ROC Rochdale
RTC Rochdale Town Centre
SHC Shaw & Compton
SPS St Peters Square
SWB St Werberghs Road Reported in error? See SWR, seen on site
SWR St Werberghs Road
TFB Trafford Bar
TRC Trafford Centre
VEL Velopark
VIC Victoria street area
VIM Victoria Metrolink, as opposed to adjacent Network Rail signalling
WFD Whitefield
WSD Wharfside
WST Weaste

Midland Metro signals

Prefixes known are PS (points indicator), S (stop signal), LOS (limit of shunt sign, used without additional number) and SS (stop signal (?), seen near Snow Hill). Level crossing and on-street stop signals do not carry any form of label.

The Edgbaston extension introduced new signal codes. These have a prefix based on the nearby station, and further prefix PS (points indicators) or suffix S (stop signals). Prefixes known at present are:

Code Area
LIB Library
unknown unknown code seen just north of Black Lake

Nottingham Tram signals

Prefixes for these are based on the electrification code, in addition to a P (points indicator) or S (stop signal). Other codes may also exist. Thus a stop signal at Phoenix Park carries the prefix PPS.

Sheffield Supertram signals

It appears that initially signals are not numbered, being on the whole just tram signals attached to road traffic lights. One stop signal labelled HB was seen at Hillsborough. Later, tram signals were labelled based on nearby stations.

Code Area
MS Meadowhall South/Tinsley

Tyne & Wear Metro signals

No evidence of any signal prefix has been found, except on the Pelaw-South Hylton section. This is controlled from Network Rail's Tyneside signalling centre with code T.

Heritage, minor and miniature railways and other 'special' signals

Signal boxes without known prefixes are excluded. Items are shown alphabetically by signal box name or, where there is no known name, by the location.

Code Signal Box Location Note
S Abbeydale South Abbeydale Miniature Railway
W Abbeydale West? Abbeydale Miniature Railway
A Abergynolwyn Talyllyn Railway
WN Acton Miniature Railway Code taken as a convenient gap in District and Piccadilly codes in Acton area, and coincidentally also suggests 'Westinghouse style N miniature power lever frame', the equipment fitted
RWN Repeater signals
A At least one signal
C Alexandra Liverpool Overhead Railway
A Alston South Tynedale Railway
AT Alton Mid Hants Railway
AJ Amwell Junction East Herts Miniature Railway Main signals
S Siding signals
AR Angel Road Malden & District Society of Model Engineers
C Ashmanaugh Railway
S
SN Avondale Railway Signals
EP Electric point machines
NR Network Rail Training Centre, Basingstoke Training signal
BE Baytree Spinney Light Railway
AL Beer Heights Light Railway Remaining (at 2014) signals near Much Natter from old signalling scheme (also has signal labelled D with no number)
C Remaining (at 2014) signals near Much Natter from old signalling scheme (also has signal labelled D with no number)
BC Bentley Central Bentley Miniature Railway
BL Bishops Lydeard West Somerset Railway
BJ Boundary Junction Chadwell Heath Miniature Railway
BJ Bridgen Training Academy Training signal
B Britannia Crossing Paignton & Dartmouth Railway
BC Code reported but not carried
BE Brookside Brookside Miniature Railway
BH Burhill Surrey Light Railway
BS Burtonshaw Barnards Miniature Railway
DC Chadwell Heath Miniature Railway
JS
PP
CL Church Lane Peak Railway Code seen on drawing, not known if carried
CN Churston Paignton & Dartmouth Railway Recontrolled to Britannia Crossing
CH Cockrow Hill Great Cockrow Railway
CL Common Lane Gartell Light Railway
CW Cranmore West East Somerset Railway
CE Crewe Heritage Centre miniature railway Shorter ride past Exeter West signal box
GL Cutteslow Park Cutteslow Park Railway, Oxford Ground level line
RL Raised level line
DD Darley Dale Peak Railway Code seen on drawing, not known if carried
DE Deeside Llangollen Railway
KJ Derby Catalis Training Training signal
DC Dereham Central Mid Norfolk Railway
DD Dingly Dell Spinney Light Railway
DR Dragon Miniature Railway, Marple
EG East Grinstead Bluebell Railway
R East Lancashire Railway Repeater signals
EL Eastleigh Lakeside Eastleigh Lakeside Railway
EH Elmdon Halt Wythall Miniature Railway
EJ Engine Shed Junction Wrexham Model Engineering Society
LW Epping Epping Signalling Museum Museum demonstration signal
RLW Museum demonstration signal
ERI Eridge Spa Valley Railway Stop boards at Eridge
GRB Unknown board labelled GRB E
ES Everglades Great Cockrow Railway
D Down direction automatic signals
DB Down branch automatic signals
DM Down main automatic signals
U Up direction automatic signals
UB Up branch automatic signals
F Falconwood Welling & District Model Engineering Society
FN Fancott Fancott Miniature Railway
FE Farr End Chadwell Heath Miniature Railway
FE Forge Crewe Heritage Centre miniature railway Longer ride with reversal near entrance
S Frimley Lodge Miniature Railway Not all signals carry a prefix
GW Glyndebourne Wood Bentley Miniature Railway
GH Greenway Halt Paignton & Dartmouth Railway
GJ Gresford Junction Wrexham Model Engineering Society
GC Grosmont Crossing North Yorkshire Moors Railway
HC Hampton Court Junction Malden & District Society of Model Engineers
H Code reported but possibly not carried
HK Hardwick Great Cockrow Railway
HT Hastingwood North Weald Miniature Railway
H Herculaneum Liverpool Overhead Railway
HW High Wycombe Holmer Green Miniature Railway
HK Horsted Keynes Bluebell Railway
H Hythe Romney Hythe & Dymchurch Railway Opened 1927
CN Ipswich Rail Tech Group Training Academy Training signal. Code from 'Claydon'
KR Kidderminster Severn Valley Railway
KC Kingscote Bluebell Railway Into use 5 February 2016?
KR Kingsland Road Amey Rail training school, Bristol Training signal
KE Kingsmere East Moors Valley Railway
DA Down direction automatic signals
UA Up direction automatic signals
KW Kingsmere West Moors Valley Railway
L Lakeside Coate Water Miniature Railway, Swindon
LD Larkswood Ridgeway Park Railway, Chingford
EH Lathalmond Railway Non-functioning heritage signal
EY Lathalmond Railway Non-functioning heritage signal
LM Little Moor Beer Heights Light Railway
E Liverpool Overhead Railway
F
S Automatic signals
MJ Mole Junction Surrey Light Railway
MB Monks Brook Eastleigh Lakeside Railway
MA Motala Swanage Railway Now removed
MN Much Natter Beer Heights Light Railway
MH Museum Halt Woodhorn Railway
Q Needham Stevington & Turvey Light Railway May also have (had) code N
NB New Bridge North Yorkshire Moors Railway
GF Ground frame controlled signals
R New Romney Romney Hythe & Dymchurch Railway Opened 1927
WIH Newby Hall Newby Hall Miniature Railway
ES East signal
WS West signal
N Norden Swanage Railway Original code, not seen on site 2025
NX Level crossing protection signals
N North Mizens Railway Controlled signals
B Shunt signals
X Track circuit controlled signals
NW North Weald Epping Ongar Railway
T Training signal beside sidings
NW North Weald North Weald Miniature Railway
ON Okehampton Dartmoor Railway Training signal
OO Old Oak Spinney Light Railway
OW Old Works Crewe Heritage Centre miniature railway Longer ride with reversal near entrance
OG Ongar Epping Ongar Railway
VO Orchard Green Junction Isle of Wight Railway Museum demonstration signal, later code ('Vic Orchard', after signalling supervisor), removed by August 2019
AF Original code ('April Fool'), soon replaced
PS Paignton South Paignton & Dartmouth Railway
PL Pardoe Lane Barnards Miniature Railway
PW Pinesway Junction Gartell Light Railway
S Pinewood Railway, Wokingham
C S
P Princes Risborough Chinnor & Princes Risborough Railway
RG Prospect Park Reading Society of Model Engineers Ground level line
RR Raised level line
QP Queens Park Paignton & Dartmouth Railway
RKHL Rainsbrook Rainsbrook Park, Rugby High level line
RKLL Low level line
S Ravensprings Miniature Railway Signals also suffixed STN (station area) and DELL (wooded area)
RR Rodham Road Dunhams Wood Railway
R Rolvenden Kent & East Sussex Railway Applied to at least one ground shunt signal
M Romney Marsh Romney Hythe & Dymchurch Railway
RN Rudyard Rudyard Lake Railway
WJ Rugby Signalling Engineering School & Technical Assessment Centre (GM Rail Services) Training signal: 33 Somers Road, Rugby site
GM Training signal: 65 Somers Road, Rugby site
S Rugeley Miniature Railway
ED Slateford Slateford Signalling School (on site of Slateford Junction) Training signal
KS
Z South Kensington London Underground Signalling School (in disused deep level tunnel) Training signal
SY Spinney Spinney Light Railway
SB Steaming Bays Wythall Miniature Railway
SP Stoke Park Guildford Miniature Railway
SPA Automatic signals
SP Sutton Sutton Life Educational Centre Track safety simulator signal
L Summerfields Miniature Railway
GL Teesside Small Gauge Railway (Eaglescliffe) Ground level line
T Thuxton Mid-Norfolk Railway
SU Tidbury Sutton Model Engineering Society Raised level track
GA Ground level track automatic signals
SG Ground level track
TWW Tunbridge Wells West Spa Valley Railway Railway
TE Tunnel East Beer Heights Light Railway Also referred to as T'Other End
T Twitchen Manor Mizens Railway Controlled signals
A Shunt signals
X Track circuit controlled signals
BL Tyttenhanger Miniature Railway
BT
CC
DDS Dingley Dell signals
MB
P
SA Station access signals
T
TE Tunnel entrance signals
TS
W
WT
NR Walsall Network Rail training school Training signal
NT Unipart Rail Demonstration signal
W Wansford Nene Valley Railway
S Waterside Railway (Canvey Island)
WR Weardale Railway
EH West Ashfield Training signal at London Underground training 'station' in West Kensington
WB Willowbank Malden & District Society of Model Engineers
W Code reported but possibly not carried
W Winchcombe Gloucestershire Warwickshire Railway Unclear whether code actually carried