| A1 |
National |
| A2 |
England & Wales |
| A3 |
London & South East |
| A4 |
Long Distance |
| A5 |
Regional |
| A6 |
Scotland |
| AO |
unknown |
| BC |
Grantrail |
| CA |
Railway DDS |
| CB |
Finance & HQ |
| CC |
College Of Railway Technology |
| CD |
AEA Technology |
| CE |
Miller Liability |
| CF |
Business Systems |
| CG |
First Procurement |
| CH |
Railpart (UK) |
| CI |
British Rail Telecommunications [Central Services agency] |
| CJ |
TCI Projects |
| CK |
Residual Works and Depots |
| CL |
Interfleet Technology |
| CM |
Engineering Link |
| CN |
WS Atkins National Train Enquiry Services |
| CO |
CMS RTAC Warrant |
| CP |
Scientifics |
| CQ |
Railtest |
| CR |
Technical Services |
| CS |
National Rail Supplies Service Centres |
| CT |
Bodycote Materials |
| CU |
Interlogic Controllers |
| CV |
WS Atkins Opal |
| CW |
National Rail Supplies |
| CX |
TCI Operational Research |
| CY |
Disagregation |
| CZ |
BRB Subsidiary Defaults |
| D1 |
Freightliner Infrastructure |
| D2 |
Freightliner Heavy Haul |
| D8 |
Freightliner Intermodal |
| DA |
English Welsh & Scottish Railway |
| DA |
Railfreight Distribution |
| DA |
DB Cargo International |
| DB |
Freightliner Intermodal |
| DH |
Freightliner Heavy Haul |
| E1 |
GWR charters |
| EA |
English Welsh & Scottish Railway |
| EA |
Transpennine Express |
| EB |
Abellio Greater Anglia [Greater Anglia] |
| EB |
Abellio East Anglia [Greater Anglia] |
| EB |
GE Trains [Greater Anglia] |
| EC |
Grand Central |
| ED |
Northern Rail |
| EE |
Heathrow Connect |
| EF |
First Greater Western [First Great Western; Great Western Railway] |
| EG |
First Capital Connect |
| EH |
XC Trains [CrossCountry] |
| EI |
Wrexham, Shropshire & Marylebone Railway |
| EJ |
London & Birmingham Railway [London Midland] |
| EJ |
West Midlands Trains [London Northwestern Railway; West Midlands Railway] |
| EJ |
WM Trains [London Northwestern Railway; West Midlands Railway] |
| EK |
London Overground Rail Operations [London Overground] |
| EK |
Arriva Rail London [London Overground] |
| EL |
Glasgow Trains |
| EM |
East Midlands Trains |
| EM |
Abellio East Midlands [East Midlands Railway] |
| EN |
Devon & Cornwall Railways |
| ES |
Serco Caledonian Sleepers |
| ET |
Govia Thameslink Railway [Thameslink; Southern; Great Northern; Gatwick Express] |
| EU |
Virtual European paths |
| EX |
GTS Rail Operations [TfL Rail] |
| EX |
MTR Corporation (Crossrail) [TfL Rail] |
| FA |
Loadhaul |
| FA |
English Welsh & Scottish Railway European Freight |
| FD |
English Welsh & Scottish Railway International |
| FE |
English Welsh & Scottish Railway [Mainline Freight] |
| FL |
English Welsh & Scottish Railway [Transrail Freight] |
| FM |
DB Schenker [Rail express systems] |
| FX |
Serco Rail Operations |
| GA |
Eurostar International |
| GA |
Eurostar (UK) |
| GB |
Rail Europe |
| GC |
IPAC |
| GD |
Eurotunnel |
| GO |
Go-Op |
| HA |
Scotrail |
| HA |
First Scotrail |
| HA |
Scotrail Railways |
| HB |
East Coast Main Line Company |
| HB |
Great North Eastern Railway |
| HB |
Intercity East Coast |
| HB |
London North Eastern Railway |
| HB |
NXEC Trains [National Express East Coast] |
| HB |
Virgin Trains East Coast |
| HC |
Arriva Trains Northern |
| HC |
Northern Spirit |
| HC |
Regional Railways North East |
| HD |
North Western Trains Company [First North Western] |
| HD |
North West Regional Railways |
| HE |
Merseyrail Electrics (2002) |
| HE |
Arriva Trains Merseyside |
| HE |
Merseyrail Electrics |
| HF |
First Trenitalia West Coast Rail [Avanti West Coast] |
| HF |
InterCity West Coast |
| HF |
West Coast Trains [Virgin Trains West Coast] |
| HG |
Central Trains |
| HH |
CrossCountry Trains [Virgin CrossCountry] |
| HI |
Midland Main Line |
| HJ |
Great Western Trains [First Great Western] |
| HK |
Wales & West Passenger Trains [Wessex Trains; Wales & West] |
| HK |
South Wales & West Railway |
| HL |
Cardiff Railway Company [Wales & Borders Trains] |
| HL |
Arriva Trains Wales |
| HL |
Keolis Amey Operations/Gweithrediadau Keolis Amey Limited [Transport for Wales] |
| HM |
Heathrow Express |
| HN |
First Great Western Link |
| HN |
Thames Trains |
| HO |
The Chiltern Railway Company |
| HP |
North London Railways |
| HP |
Silverlink Train Services |
| HQ |
West Anglia & Great Northern |
| HR |
Great Eastern Railway [First Great Eastern] |
| HS |
Anglia Railways Train Services |
| HT |
c2c rail |
| HU |
SE Trains [Southeastern] |
| HU |
London & South Eastern Railway [Southeastern] |
| HU |
South Eastern Trains |
| HU |
Connex South Eastern |
| HV |
Gatwick Express |
| HW |
Connex South Central |
| HW |
New Southern Railway |
| HW |
South Central |
| HW |
Southern Railway |
| HX |
Thameslink Rail |
| HY |
First MTR South Western Trains [South Western Railway] |
| HY |
South Western Railway |
| HY |
South West Trains |
| HY |
Stagecoach South Western Trains [South West Trains] |
| HZ |
Island Line |
| IS |
GB Railways |
| JA |
First Info |
| JB |
On Time Design |
| JC |
Rail Property |
| JD |
P&MM Railpart Doncaster |
| JE |
Red Funnel |
| JF |
P&MM Infrastructure |
| JG |
NXEC Telesales |
| JH |
former Bus HQ |
| JI |
totaljourney.com |
| JJ |
First Procurement Association |
| JK |
Qjump |
| JL |
London offices |
| JM |
Rail Europe 4a |
| JN |
Newcastle Telesales |
| JO |
Rail Gourmet |
| JP |
ATOC |
| JQ |
ATOC |
| JR |
Rail Settlement Plan [RSP] |
| JS |
FCM Travel (JS) |
| JT |
Travel Agents |
| JU |
Charing Cross Canteen |
| JV |
Trainline |
| JW |
Harry Weeks Travel |
| JX |
A G Gates |
| JY |
Clyde Travel |
| JZ |
BRB Subsidiary Default |
| KA |
Bombardier East Ham |
| KB |
Alstom Train Services Glasgow |
| KC |
Bombardier Aylesbury |
| KD |
Adtranz Doncaster |
| KE |
Alstom Eastleigh |
| KF |
Maintrain |
| KG |
Railcare Glasgow |
| KH |
Siemens |
| KI |
Alstom Chester |
| KJ |
Alstom Shields |
| KK |
Hunslet-Barclay |
| KL |
London And North Western Railway |
| KM |
Marcroft |
| KN |
Adtranz Manchester |
| KO |
Adtranz Etches Park |
| KP |
Allied Inspection |
| KQ |
Pullman Rail |
| KR |
West Coast Traincare |
| KS |
Adtranz Norwich |
| KT |
Adtranz Hornsey |
| KU |
Prorail |
| KV |
AdtranzConnex Joint Venture |
| KW |
Railcare Wolverton |
| KX |
Railcare |
| KY |
Brush Traction |
| KZ |
Adtranz HQ |
| LA |
Transrail Freight |
| LB |
EWS Railway Direct |
| LC |
Loram |
| LD |
East Coast Trains [Lumo] |
| LF |
Grand Union Trains |
| LG |
Legge Infrastructure Services |
| LN |
Great North Western Railway |
| LR |
Network Rail On Track Machines |
| LS |
Locomotive Services (TOC) |
| MA |
Rail express systems |
| MB |
Special Trains Unit |
| MC |
Rail Express Systems special trains |
| MD |
unknown |
| MV |
Varamis Rail |
| NA |
Passenger Disputed Minutes |
| NB |
Freight Disputed Minutes |
| NC |
Contractor Disputed Minutes |
| ND |
unknown |
| NE |
unknown |
| NF |
unknown |
| NI |
unknown |
| NP |
National Power |
| NR |
Network Rail Reserved Pathings (Non QJ) |
| OA |
BT Police |
| OD |
Lorne Stewart |
| OE |
Sema Group |
| OG |
CAP Gemini |
| P1 |
GB Railfreight engineering trains |
| P2 |
Victa Westlink Rail passenger charters |
| P3 |
Advenza Cotswolds passenger charters |
| P4 |
GB Railfreight charters |
| P5 |
West Coast Railway Company infrastructure |
| P6 |
Devon & Cornwall Railway infrastructure |
| P8 |
Rail Operations Group charters |
| PA |
West Coast Railway Company |
| PB |
Rail Charter Services |
| PC |
Venice Simplon-Orient-Express |
| PD |
Mendip Rail |
| PE |
GB Railfreight |
| PF |
Hull Trains Company |
| PG |
Nexus |
| PG |
DB Regio Tyne & Wear |
| PH |
Rail Operations Group |
| PI |
Advenza Freight |
| PJ |
Merlin Rail |
| PJ |
Victa Westlink Rail |
| PK |
Pre Metro Operations |
| PL |
Cotswold Rail |
| PM |
Merlin Rail |
| PM |
On Route Logistics UK |
| PN |
Freight Europe |
| PO |
Devon & Cornwall Railways |
| PP |
Greater Manchester PTE |
| PQ |
Riviera Trains |
| PR |
North Yorkshire Moors Railway |
| PS |
SNCF Freight |
| PT |
Europorte Channel |
| PV |
Victa Railfreight |
| PX |
Europhoenix |
| PZ |
Wessex (final use) |
| QA |
Wrong TSC |
| QA |
Network Rail Head Quarters |
| QB |
Network Rail Sussex |
| QC |
Network Rail Wessex |
| QD |
Network Rail Western |
| QE |
Network Rail Midlands/Central |
| QF |
Network Rail North West |
| QG |
Network Rail London North East |
| QH |
Network Rail Anglia |
| QI |
Network Rail East Coast |
| QJ |
Network Rail Virtual Freight Co |
| QJ |
Network Rail Eastern |
| QK |
Network Rail East Coast Main Line |
| QK |
Network Rail Southern |
| QL |
Network Rail Scotland |
| QM |
Network Rail Kent |
| QN |
Network Rail Property |
| QN |
Network Rail West Coast Main Line South |
| QO |
Network Rail External Customer |
| QP |
Network Rail Major Projects |
| QQ |
Network Rail Midland & Continental (HS1) |
| QR |
Network Rail London North West |
| QR |
Network Rail London North West & Central |
| QS |
Network Rail Ex RSSB |
| QS |
Network Rail Scotland |
| QT |
Network Rail South East Assets Territory |
| QU |
Network Rail Information Systems |
| QU |
Network Rail Western & Wales |
| QV |
Network Rail Midland & Continental |
| QV |
Network Rail East Midlands |
| QW |
Network Rail Wales |
| QY |
Network Rail UK Private Infrastructure |
| QZ |
Network Rail Non UK |
| R1 |
Fastline infrastructure |
| R2 |
Colas infrastructure |
| R4 |
Harsco Rail freight |
| RA |
Balfour Beatty Rail renewals |
| RB |
Carillion Rail |
| RB |
GTRM |
| RC |
Fastline maintenance |
| RC |
Jarvis Facilities |
| RD |
First Engineering |
| RD |
Swietelsky Babcock Rail (SB Rail) |
| RE |
Amey Rail |
| RF |
Balfour Beatty 'Reg Projects Lnd' |
| RG |
Amec |
| RG |
Colas Rail freight |
| RH |
Volker Rail |
| RH |
Grantrail |
| RI |
Balfour Beatty |
| RJ |
Fastline Freight |
| RJ |
Jarvis Track Renewal Company |
| RK |
Centrac |
| RL |
Northern Track Renewal Unit |
| RL |
Jarvis Fastline (Northern) |
| RM |
Scotland Track Renewals |
| RM |
Jarvis Fastline (Scotland) |
| RM |
Network Rail Roz Schedule Test/Internal Testing |
| RN |
Western Track Renewals |
| RN |
Jarvis Fastline (Western) |
| RO |
Balfour Beatty Civil Engineering |
| RO |
First Engineering |
| RP |
Adtranz Aylesbury |
| RP |
Balfour Beatty |
| RQ |
Carillion (CTRL Phase 1) |
| RR |
JSD Research & Development |
| RS |
Serco Rail Maintenance |
| RT |
Harsco Rail |
| RU |
Jarvis non-rail |
| RU |
Seco Rail |
| RV |
CEDAC London |
| RV |
WS Atkins CEDAC |
| RW |
Amey Seco |
| RX |
BPE |
| RY |
Power Track |
| RZ |
Balfour Beatty Rail Plant |
| SA |
Eversholt Rail |
| SB |
Porterbrook |
| SC |
Angel Train Contracts |
| SD |
Serco Management Services |
| SD |
Serco Rail Operations |
| SE |
Serco Support Services |
| SF |
Mainline Station Cleaners |
| SG |
Serco (RT99) |
| SH |
Serco Test Services |
| SI |
Serco Rail Maintenance |
| SJ |
South Yorkshire Supertram |
| SM |
Controller |
| SO |
SLC Operations |
| SO |
RailAdventure UK |
| SP |
The Swanage Railway Company |
| TA |
British Rail Telecommunications |
| TK |
Serco Edinburgh Telesales |
| TL |
London Call Centre |
| TN |
BT 'Conn In Bus' |
| TR |
National Rail 'Com' Centre |
| TS |
Scotland Call Centre |
| TY |
Vintage Trains |
| UB |
Thales |
| UC |
Interfleet Technology |
| UD |
Engineering Link |
| UE |
Network Engineering Services |
| UF |
ISS (London) |
| UK |
Raildirect |
| US |
RSSB |
| UT |
LTS Rail |
| VA |
Red Star Parcels |
| VB |
Adtranz Chart Leacon |
| VC |
Adtranz Ilford |
| VD |
Rail express systems special trains |
| VE |
Rail Vehicle Engineering |
| VF |
Owen Williams Railways |
| VG |
Eversholt Rail |
| VG |
HSBC Rail UK |
| VH |
Angel Train Contracts |
| VI |
Porterbrook Leasing |
| VJ |
Occupational Health |
| VK |
Catalys Rail Training |
| VL |
Westinghouse Signals |
| VM |
Fragonset Railways |
| VM |
Rail express systems |
| VN |
Rail Projects |
| VO |
Materials Engineering |
| VP |
Quality & Safety |
| VQ |
CEDG York |
| VR |
Scott Wilson Railways |
| VS |
Scott Wilson Railways |
| VT |
WS Atkins CEDAC |
| VU |
James Scott-BPE |
| VV |
WS Atkins Rail |
| VW |
Adtranz Signals |
| VX |
Rail Pension Management |
| VY |
Railpen Investments |
| VZ |
Pension Trustees |
| W1 |
DB Cargo Charters |
| WA |
DB Cargo |
| WA |
DB Schenker |
| WA |
English Welsh & Scottish Railway |
| X1 |
Direct Rail Services charters |
| X2 |
Direct Rail Services infrastructure |
| XA |
RSL Use Only |
| XB |
LUL District Line (Wimbledon) |
| XC |
LUL Bakerloo Line (Harrow) |
| XD |
'BR' Over LUL Line |
| XE |
LUL District Line (Richmond) |
| XF |
Balfour Beatty Rail Maintenance |
| XG |
National Power |
| XH |
Direct Rail Services |
| XI |
ICL |
| XJ |
Ffestiniog Railway |
| XM |
LUL Metropolitan Line (Croxley Rail Link) |
| XN |
OCE (UK) |
| XP |
Peak Rail |
| XT |
Travel Agents |
| XU |
Union Pacific |
| XV |
Tiphook Rail |
| XW |
Waterman Railways |
| XX |
P&O freight customers |
| XX |
Wrong TSC |
| YA |
Group Head Quarters Non SAU |
| YB |
Residual Central Services |
| YC |
Property Board |
| YD |
BR Residual Body |
| YG |
Hanson & Hall Rail Services |
| ZA |
Source System Control |
| ZB |
Corporate |
| ZB |
Alliance Rail |
| ZC |
Source System Disaggregation |
| ZD |
Disaggregation PC |
| ZE |
Disaggregation |
| ZF |
Passenger Accounting |
| ZG |
Rail Settlement Plan 1 & 2 |
| ZH |
Rail Settlement Plan 3 |
| ZJ |
SRTL ltd |
| ZO |
DFT |
| ZT |
Scottish Executive/'Sta' |
| ZZ |
DB Schenker Rail Infrastructure Transport System [RITS] |