Signal box prefix codes

A (hopefully) comprehensive listing

'Boxes beginning P

Last update 1 May 2025

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Please select a starting letter from the links below:

Code Signal Box Note ELRMileage Opened Closed Control to
V Paddington Arrival Box possibly also known as Paddington Suburban. Severely damaged by fire. Code used on Hammersmith & City lines HTH0m 20ch MLN10m 20ch 13 August 1933 25 November 1938 Paddington Arrival [temporary]
FRV Hammersmith & City fog repeater signals
FRVX Hammersmith & City fog repeater advance starting boards
RV Hammersmith & City repeater signals
VX Hammersmith & City advance starting boards
EC Code used on Engine & Carriage line unclear if EC signals controlled from Paddington Arrival
Paddington Arrival [temporary] HTH0m 20ch MLN10m 20ch 13 December 1938 1 July 1939 Paddington Arrival [reopened] (V)
V Paddington Arrival [reopened] Box possibly also known as Paddington Suburban. Code used on Hammersmith & City lines HTH0m 20ch MLN10m 20ch 2 July 1939 19 November 1967 Old Oak Common (OO), Edgware Road [London Underground] (OP)
FRV Hammersmith & City fog repeater signals
FRVX Hammersmith & City fog repeater advance starting boards
RV Hammersmith & City repeater signals
VX Hammersmith & City advance starting boards
EC Code used on Engine & Carriage line unclear if EC signals controlled from Paddington Arrival
Paddington Suburban See Paddington Arrival
QE Paddock Wood Named Paddock Wood B to 26 June 1932 Unclear whether code used XTD34m 74ch 26 June 1898 1 April 1962 Tonbridge (PE)
Paddock Wood B See Paddock Wood
Padnal Burnt down 20 December 1989 ETN73m 17ch 1887 21 February 1990 Cambridge (CA)
PN Paignton TOR222m 04ch 1890 26 March 1988 Paignton South
DT Down Torbay line automatic signals
UT Up Torbay line automatic signals
PN Paignton [new] TOR222m 10ch 5 August 1989
Paignton South TOR222m 22ch August 1989 Paignton [new] (PN)
P Paisley Code used from 1966 AYR1≈6m 30ch 14 November 1966 1 September 1985 Paisley [new] (P)
P Paisley [new] Former Paisley signals AYR16m 30ch 1 September 1985 25 December 2011 West Of Scotland Signalling Centre (GP, GPA, GPB, GPD, GPE, GPG, GPH, GPK, GPL, GPU, GPW)
PA Ayr interlocking
PB Barassie interlocking
PE Elderslie interlocking. Code used from 1985
PG Glengarnock interlocking. Code used from 1985
PH Hunterston interlocking. Code used from 9 November 1986
PK Kilwinning interlocking. Code used from 1986
PKR Kilwinning interlocking banner repeater signals
PU Gourock interlocking. Code used from 27 March 1985
R Banner repeater signals
P Paisley St James Temporary code from 14 November 1966 for two signals, until taken over by Paisley GOU2≈108m 46ch 18 August 1902 11 December 1966 Paisley (P)
P Pangbourne MLN141m 56ch 1893 9 May 1965 Reading (R)
PF Pantyffynnon Named Pantyffynnon South to 13 March 1966 LLA10m 01ch December 1892
P
CWL Central Wales Line points indicators. Code used from 2010
KN Knighton points indicators
LO Llandeilo points indicators
LR Llandrindod Wells points indicators
LV Llandovery points indicators
LW Llanwrtyd points indicators
VOT Llandovery points indicators. Code used from 2010
Pantyffynnon South See Pantyffynnon
PR Par MLN3281m 69ch 1879 11 March 2024 Exeter (CL)
PB Parbold WBS324m 49ch 1877
PD
P Parkeston MAH68m 63ch 1987
P Parkeston [temporary panel] MAH≈68m 63ch 1 December 1985 1987 Parkeston (P)
PE Parkeston East MAH69m 18ch 1882 18 November 1973 Parkeston West (PW)?
PG Parkeston Goods Junction MAH68m 18ch 1934 1 December 1985 Parkeston [temporary panel] (P)
PW Parkeston West MAH68m 69ch 1934 1 December 1985 Parkeston [temporary panel] (P)
P Parkgate Codes used from February 1966 ECM544m 67ch 13 May 1972 Darlington (D)
D Down line automatic signals
U Up line automatic signals
P Parkgate Junction Code used from 1965 TJC3163m 18ch March 1902 29 July 1979 Sheffield (S)
P Parkhead North Junction Code used from 1960 ARG21m 72ch 16 August 1875 28 July 1991 Yoker (YF)
PJ Park Junction NWN0m 54ch October 1885 15 November 2023✖last train; official closure 4 December 2023 Wales Rail Operating Centre (PJ)
DM Down main line automatic signals
UM Up main line automatic signals
D Park Junction Down line automatic signals ALP≈5m 03ch June 1939 25 March 1984 Line closed
U Up line automatic signals
D Park Lane Gate box and ground frame: line controlled by Liverpool Street [new] (L) HDT13m 15ch 28 November 2012 Liverpool Street [new] (L)
U
PR Park Royal Formerly named Park Royal West ANL4m 64ch May 1903 15 July 1979 Old Oak Common [new panel] (OO)
Park Royal West See Park Royal
M Parks Bridge Junction XTD6m 17ch 30 June 1929 8 February 1976 London Bridge (L)
PS Park South CBC133m 06ch 18 June 1883
P Parkwood MAC339m 39ch 17 October 1903 April 1966 Wadsley Bridge (WY)/ Neepsend (N)
PH Parsons Heath Code used by 1962 LTN154m 06ch by November 1903 24 April 1983 Colchester (CO)
PS Parson Street Junction Code used from April 1970 MLN1120m 33ch 13 November 1932 4 December 1971 Bristol (B)
P Partick Junction Code used from 1935 NEM33m 37ch 1 December 1886 3 July 1960 Hyndland (HY)
PS Parton Station Code used from 2008 CBC21m 41ch 1879 31 May 2010 Bransty (BY)
PNR Distant signals. Code seen on 2006 signalling plan
PB Pass Of Brander Automatic 'rock' signals, not a control point in the usual sense OBN2 January 1882
P Pasture Street Code used from 26 September 1993 MAC3109m 49ch 29 April 1962 30 December 2015 York Rail Operating Centre (P)
Patchway BSW5m 70ch 19 October 1902 20 February 1971 Bristol (B)
Peak Forest South CNB1163m 57ch 1925
P Peckfield HUL411m 17ch ≈1873 19 April 1997 Church Fenton (CF)
PR Distant signals
TC Peckham Rye Named Peckham Rye C to 20 February 1965 BTH13m 45ch CAT4m 79ch 1899 13 April 1969 Bricklayers Arms Junction (F)
A Automatic signals
Peckham Rye C See Peckham Rye
PD Pegswood Code used from December 1962 ECM7≈18m 70ch 20 February 1972 Morpeth (M)
D Down line automatic signals
RU Repeater for up line automatic signals
U Up line automatic signals
P Pelaw LEN3≈98m 13ch 2 October 1960 12? September 1982 Gateshead (G)
PW Code used by 1969 until closure
D Down direction automatic signals
U Up direction automatic signals
PS Pelham Street Signals to east of signal box SPD382m 28ch 1874 31 August 2008 Lincoln Control Centre (LG/BL/SL)
P Signals to west of signal box
Pembrey See Pembury & Burry Port
PY Pembury & Burry Port Also known as Pembrey. Code used by 2 December 1973 SWM2228m 70ch 1907 Wales Rail Operating Centre (PT) (planned)
PE Penarth Curve East No 1 Ground Frame BRY0m 23ch 28 March 1966
PN Penarth Curve North Downgraded to ground frame 26 March 1966, closed, reopened 13 February 1988 RAD0m 48ch October 1933 27 March 1966 Cardiff (C)
PC Pencoed (East) Code used before downgrading to gate box 13 September 1965: line controlled by Port Talbot (PT) SWM2186m 56ch 1905 31 March 2007✖last train; official closure 13 April 2007 Port Talbot [temporary] (PT)
EF Penge East VIR7m 12ch 25 February 1968 Beckenham Junction (EG)
KC Penge West Downgraded to ground frame 8 October 1950 LBW7m 14ch 15 October 1911 21 August 1966 London Bridge (E)
P Penistone Named Huddersfield Junction to 23 April 1989 Code used from renaming PED128m 37ch PEH13m 42ch MAC128m 37ch 1887 9 April 1998 Barnsley (BY)
HJ Code used when named Huddersfield Junction
H Code present in 1969
PG Penistone Goods MAC127m 59ch 13 November 1899 18 July 1981 Line closed
PW Penistone West MAC128m 21ch 14 May 1893 February 1966 Huddersfield Junction (HJ)
PE Penkridge RBS3 Stafford No 4 (SD4)
PR Penmaenmawr Code used by 1987 CNH3228m 63ch 13 December 1952
PD Penyffordd Code in use by December 2018 WDB17m 41ch 17 December 1972
PZ Penzance MLN4326m 32ch 24 April 1938
SE One signal at Long Rock depot
LR Penzance Long Rock depot MLN4 2016?
PM Percy Main ?5m 78ch from Newcastle 27 March 1955? 10 August 1980? Line transferred to Metro
P Perth Code used from 1962 HGL1151m 05ch SCM520m 79ch 27 March 1962
H Perth Hump Yard Control Tower Code for hump signals only HGL1≈152m 65ch 31 July 1961 Perth (P)
P Peterborough PMJ22m 04ch 3 December 1972 28 August 2023 York Rail Operating Centre (P)
PBO Unclear if code carried. Stamford route
PE Peterborough East EMP100m 07ch 17 April 1932 10 June 1973 Peterborough (P)
PN Peterborough North Reduced to ground frame 20 August 1972 ECM1≈77m 04ch 6 April 1874 3 December 1972 Peterborough (P)
PF Petersfield WPH154m 65ch ≈1890 November 2025 (planned) Basingstoke Rail Operating Centre (BEP) (planned)
DPF Distant to controlled signal
WA Automatic signals
DWA Distant to automatic signal
CCV Pevensey WJB23m 03ch 1876 late on 13 February 2015✖delayed from 22 November 2013 Three Bridges Rail Operating Centre (TEB)
Philips Park No 1 PPA11m 70ch 1889 15 September 1998 Manchester North (MN)
Philips Park No 2 PPA12m 19ch 1889 15 September 1998 Manchester North (MN)
PE Piccadilly East Temporary 'box CMP2188m 45ch 21 December 1998 2 January 1999 Manchester Piccadilly (MP)
PL Picketts Lock BGK8m 69ch 1910 10 March 1969 Brimsdown (BD)
D Down line automatic signals
U Up line automatic signals
P Picton LEN352m 31ch 1873 29 November 1997 Low Gates (LG)
PN Code used by 1988
D Down line automatic signals
U Up line automatic signals
PR Picton Road Junction EWG ≈23 May 1982 Edge Hill (EH)
P Pilmoor Named Sessay Wood to 19 February 1943, then Pilmoor South to 15 May 1960 Code used from final renaming ECM5≈15m 27ch 12 March 1933 28 July 1985 Tollerton (T)
D Down line controlled and automatic signals. Code used from opening to 15 May 1960
D Down line automatic signals. Code used from 15 May 1960 to 21 June 1971
DF Down fast line automatic signals. Code used from 19 September 1965
DS Down slow line automatic signals. Code used from 19 September 1965
U Up line controlled and automatic signals. Code used from opening to 15 May 1960. Slow lines have suffix S
U Up line automatic signals. Code used from 15 May 1960 to 21 June 1971. Slow lines have suffix S
UF Up fast line automatic signals. Code used from 21 June 1971
US Up slow line automatic signals. Code used from 21 June 1971
Pilmoor South See Pilmoor
PJ Pilning Junction Code used from 22 February 1971 BSW9m 13ch March 1901 13 March 1971 Bristol (B)
PS Pilning Station Code in use by July 1969 BSW9m 40ch 1 September 1886 13 March 1971 Newport (N)
PN Pinxton Temporary closure 18 January 1997 to ?? resulting from vandalism. 'Box moved to Barrow Hill Roundhouse 12 June 2008 PBS1135m 47ch 24 January 1897 6 August 2007 East Midlands Control Centre (PK)
P Pirton Crossing Named Pirton Sidings to 10 March 1969 when downgraded to gate box Line controlled by Gloucester (GP). BAG270m 52ch 15 October 1933 by 1995 Gloucester (G)
GP Code used from 14 May 1977
Pirton Sidings See Pirton Crossing
PT Pitlochry Code used from 2002 HGL228m 31ch 1911 26 March 2019 Stanley Junction (SJP)
PT Pitsea Formerly named Pitsea Junction FSS226m 43ch TLL32m 38ch 1960 8 April 1996 Upminster IECC (UR)
U Up line automatic signals
PJ Code when named Pitsea Junction
RPJ Repeater signals
Pitsea Junction See Pitsea
P Plaistow FSS14m 38ch ? 7 May 1960 in part; 1 May 1961 remainder Barking [LUL] (FF) in part; Barking (BK) remainder
PJ Plean Junction Code used from 1999 SCM3114m 26ch ≈1870 30 June 2008✖delayed from 28 April 2008 Larbert North (LN)
PJ Pleck Junction Unclear if code carried BJW25m 24ch ? 1965 Walsall (WL)
EBD Pluckley XTD50m 37ch by 1874 17 December 1967 Ashford (UE)
PY Plumley West CDM218m 07ch 1908
P Plumpton Code not carried. Downgraded to gate box 13 February 1985 (controlled signals T645/P6 and T800/P20): line controlled by Three Bridges (T) KJE144m 48ch 1891 8 February 2016✖delayed from 24 February 2014 Three Bridges [new] (T)
PN Plumpton CGJ7≈56m 21ch 3 March 1973 Carlisle (CE)
Plumpton Junction CBC117m 58ch 1898 19 March 2000 Ulverston (UN)
PD Plumstead NKL10m 17ch 2 December 1900 1 November 1970 Dartford (D)
P Plymouth MLN1246m 04ch 26 November 1960
DM Down main line automatic signals
PH Plymouth to Hemerdon section. Code used from 18 March 2024
UM Up main line automatic signals
MB Plymouth Millbay Downgraded to ground frame 14 December 1969 MLN1246m 48ch June 1914 30 June 1971✖last train Line closed
WBD Point Pleasant Junction RDG15m 10ch 1 July 1889 16 September 1990 Wimbledon (W)
WA Automatic signals
WDZ Pokesdown BML2106m 32ch 27 April 1930 3 December 1972 Bournemouth (WFB)
WA Automatic signals
PG Polegate Demolished 12 November 2016 KJE319m 33ch 1883 late on 13 February 2015✖delayed from 22 November 2013 Three Bridges Rail Operating Centre (TEB)
PH Polesworth LEC2106m 38ch 22 July 1990 Nuneaton (NN)
PN Pollokshaws North Downgraded to ground frame 24 February 1974 GBK2m 29ch 25 November 1900 15 June 1975 Glasgow Central (G)
N Polmadie Depot North end signals (also had suffix E and X for entrance and exit signals) 26 November 1995?
S South end signals (also had suffix E and X for entrance and exit signals)
Polmaise SCM3116m 62ch 27 October 1905 7 December 1997 Stirling Middle (SM)
P Polmont EGM124m 60ch 12 March 1979 25 November 2012 Edinburgh (EPJ/EPB)
PB Bo'ness interlocking area. Code used from 1979
PJ Polmont Junction EGM1≈24m 60ch 1872 12 March 1979 Polmont (P/PB)
P Pontefract East WAG1≈57m 43ch 21 November 1968 Knottingley (K)
R Distant signals
PS Pontefract South SMJ24m 44ch 1981? Ferrybridge (F)
P
D Down line automatic signals
R Distant signals
U Up line automatic signals
P Pontrilas HNL111m 14ch 1880 Wales Rail Operating Centre (NS) (planned)
PS
P Pontypridd CAM13m 09ch THT13m 09ch 18 September 1902 inspection date 19 October 1998 Radyr (VR)
PJ Code used by 4 September 1977
PO Poole Named Poole B to 15 November 1977 BML2113m 75ch 1897 19 May 2014 Basingstoke Signalling Control Centre (PW)
WFC Poole A BML2113m 51ch 1897 15 November 1977 Poole (PO)
Poole B See Poole
Poplar Farm Gate box: line controlled from Attleborough (A/AB) ETN107m 21ch 2 December 2012 Cambridge (EN)
P Poppleton HAY12m 75ch ≈1870
P Port Glasgow Temporary code from 27 November 1966 for two signals, until taken over by Paisley GOU2120m 33ch 12 February 1967 Paisley (P)
Porth THT16m 13ch 31 March 1981 19 October 1998 Radyr (VR)
Portland Street Gate box: line controlled by Southport Station (ST) HXS318m 00ch 28 October 1990 1994 Merseyrail (ML)
P Portobello Temporary panel ECM83m 27ch 6 May 1973 26 June 1977 Edinburgh (EP)
EP
PR Banner repeater signals
EPR Banner repeater signals
PE Portobello East ECM83m 29ch 26 September 1909 6 May 1973 Portobello (P)
PJ Portobello Junction MLN11m 30ch 1880 18 September 1967 Old Oak Common [new panel] (OO)
P Port of Tyne Authority GLT
CCF Portslade BLI12m 79ch 1877 14 May 1988 Lancing (LG)
PW Portsmouth WPH244m 29ch 7 April 1968 5 February 2007 in part; 29 October 2007 remainder Portsmouth Harbour temporary panel (PH) in part; Havant (HT) remainder
WA Automatic signals
QW Portsmouth Harbour WPH245m 20ch 2 October 1876 21 August 1941 Portsmouth Harbour temporary panel (QW)
QW Portsmouth Harbour temporary panel WPH2≈45m 20ch 21 August 1941 1 June 1946 Portsmouth Harbour (QW)
QW Portsmouth Harbour WPH245m 24ch 1 June 1946 21 April 1968 Portsmouth (PW)
PH Portsmouth Harbour temporary panel In old Portsmouth Harbour 'box (retained as relay room) WPH245m 24ch 4 February 2007 29 October 2007✖delayed from 19 March 2007 Havant (HT)
PW Portsmouth Yard WPH244m 32ch 1876 7 April 1968 Portsmouth (PW)
PS Port Sunlight Sidings Formerly named Lever Brothers Sidings CRR2≈11m 35ch 1902 2 November 1986 Rock Ferry (RF)
PT Port Talbot SWM2202m 49ch 22 September 1963 13 April 2007 Port Talbot [temporary] (PT)
DD Down Swansea District line automatic signals
DG Down goods line automatic signals
DM Down main line automatic signals
UD Up Swansea District line automatic signals
UM Up main line automatic signals
V Swansea area shunt signals unclear whether this applied to Port Talbot, or to a separate Swansea 'box
PT Port Talbot [temporary] SWM2≈202m 49ch 13 April 2007 20 May 2007 Port Talbot [reopened] (PT)
PT Port Talbot [reopened] SWM2202m 49ch 20 May 2007 4 March 2019 in part 22 May 2023 in part Wales Rail Operating Centre (PT) Port Talbot Control Centre (PT)
PT Port Talbot Control Centre SWM2202m 49ch? 22 May 2023
P Possilpark MRL12m 51ch 6 March 1977 Cowlairs (CE)
PC Potteric Carr ECM1154m 29ch February 1909 20 May 1979 Decoy No 1 (DY)
D Potters Bar Down direction automatic signals ECM112m 52ch 30 September 1886 27 March 1955 Potters Bar [new] (PB)
PB Potters Bar [new] ECM112m 52ch 27 March 1955 25 March 1973 New Barnet (NB)
D Down line automatic signals
DF Down fast line automatic signals
DS Down slow line automatic signals
R Repeater signals
U Up line automatic signals
UF Up fast line automatic signals
US Up slow line automatic signals
PT Poulton Named Poulton No 3 to 17 December 1977 PBN14m 44ch 1896 10 November 2017✖last train; official closure 26 March 2018 Manchester Rail Operating Centre (BL)
Poulton No 3 See Poulton
PJ Pouparts Junction VTB12m 08ch 9 June 1895 12 October 1952 Clapham Junction B (EC)
PH Power House CWJ7m 27ch 10 December 1988 Willesden Suburban (WS)
RPH Repeater signals
PS Pratts Sidings Shunt Frame SCQ1 9 April 1972 18 February 1985 Stoke on Trent [panel] (SE)
PS Prees SYC18m 40ch 1881 12 October 2013 South Wales Control Centre (SC)
PT Prescot SBH11m 57ch 1954 24 September 2012 St Helens Station (SH)
PN Prestatyn Formerly named Prestatyn No 2 Code carried by at least two signals CNH3205m 52ch March 1897 late on 23 March 2018✖last train; official closure 26 March 2018 Wales Rail Operating Centre (FH)
Prestatyn No 2 See Prestatyn
PN Preston CGJ60m 41ch 22 October 1972
PI Points indicators at Morecambe. Code used from 10 December 2012
R Repeater signals
P Preston Le Skerne ECM5≈49m 49ch February 1966 Ferryhill No 3 (F)/ Parkgate (P)
P Prestonpans Code used from 1977 ECM89m 43ch 15 May 1904 11 September 1977 Edinburgh (EM)
CC Preston Park Named Preston Park South to 16 October 1932 VTB349m 28ch 25 May 1879 17 March 1985 Three Bridges [new] (T)
Preston Park South See Preston Park
Prestwich MVB24m 34ch 17 August 1991 Line transferred to Manchester Metrolink
P Prestwick AYR637m 27ch 1928 7 April 1985 Ayr Local Signalling Panel (A)
P Prince Of Wales Named Prince Of Wales Sidings to 21 November 1968 Closed through fire damage CPM156m 66ch 1912 22 October 1995 Prince Of Wales [temporary box] (P)
POW Unclear whether code used
Also had draw-ahead signals in colliery sidings lettered A to E, with no number
P Prince Of Wales [temporary box] CPM1≈56m 66ch 1 November 1995 9 March 1996 Prince Of Wales [reopened] (P)
P Prince Of Wales [reopened] CPM156m 66ch 10 March 1996 9 September 2024 Ferrybridge [new] (FE)
POW Unclear whether code used
Also had draw-ahead signals in colliery sidings lettered A to E, with no number
Prince Of Wales Sidings See Prince Of Wales
PE Princes End PRN1m 63ch 14 October 1914 3 April 1981 Line closed
P Princes Risborough Named Princes Risborough North to 15 September 1968 NAJ224m 50ch 1905 12 March 1991 Marylebone [new] (ME)
PR
Princes Risborough North See Princes Risborough
P Priory Junction HAJ1m 78ch May 1984 Ashburys (AS)
CD Prologis Park Stop boards. Both codes reported, likely only one used ?
DC
PH Proof House Junction RBS1112m 24ch 4 June 1966 Birmingham New Street (NS)
PE Prudhoe Code used from 6 April 2002 NEC210m 49ch 1872
P Original code
PH Pulborough TBH149m 74ch 1878 17 March 2014✖delayed from 25 October 2013 Three Bridges [new] (T)
P Purfleet TLL16m 01ch 26 October 1924 25 May 1996 Upminster IECC (UR)
PRR Purfleet Rifle Range TLL15m 27ch Upminster IECC (UR)
CU Purley VTB213m 41ch 8 May 1955 14 January 1984 Three Bridges [new] (T)
CA Automatic signals
DCA Distant to automatic signals
DCU Distant signals
BP Puxton & Worle Downgraded to gate box 29 January 1972 (also controls Huish): line controlled by Bristol (B). Code used from 16 December 1973. Controls four signals total MLN1134m 00ch 1916
PX Purton Common Gate box: line controlled by Swindon (SN) SWM1 12 May 1981 Swindon (SN)
Pwllheli West Downgraded to ground frame DJP132m 57ch 1907
PR Pyewipe Road PYE24m 20ch 1958
PW Code shown on signalling plan
PE Pyle East Named Pyle Junction to 7 March 1947 SWM2195m 71ch 1900 11 September 1965 Port Talbot (PT)
Pyle Junction See Pyle East
PW Pyle West SWM2196m 51ch 7 March 1947 11 September 1965 Port Talbot (PT)