| Code | Name | Region |
|---|---|---|
| GBCGB | Coldingham | SCB |
| GBCDS | Coldstream | SCB |
| GBCED | Coleford | GLS |
| GBCOF | Coleford | SOM |
| GBOET | Coleorton | LEC |
| GBCLR | Coleraine | CLR |
| GBCEN | Colerne | WIL |
| GBZAQ | Coleshill | OXF |
| GBCLL | Coleshill | WAR |
| GBCVA | Colintraive | AGB |
| GBOLL | Coll | |
| GBCAF | Collafirth | ZET |
| GBCL8 | Collessie | FIF |
| GBCIT | Collieston | ABD |
| GBCBR | Colnbrook | SRY |
| GBCLZ | Colne | CAM |
| GBCKX | Clydebank/exeter | |
| GBCYP | Clydeport | NAY |
| GBCYD | Clynderwen | PEM |
| GBCYM | Clyst Saint Mary | DEV |
| GBCOD | Coalisland | DGN |
| GBCOA | Coalville | LEC |
| GBCOT | Coatbridge | NLK |
| GBCBH | Cobham | KEN |
| GBCOB | Cobham | SRY |
| GBCKP | Cockburnspath | SCB |
| GBCNZ | Cockenzie | ELN |
| GBCKM | Cockermouth | CMA |
| GBCCF | Cockfosters | BNE |
| GBCKC | Cockley Cley | NFK |
| GBCQQ | Cockwood | |
| GBONA | Coddenham | SFK |
| GBCSM | Codford Saint Mary | WIL |
| GBXCD | Codsall | STS |
| GBCGN | Cogenhoe | NTH |
| GBCOG | Coggeshall | ESS |
| GBQZL | Clevedon | NSM |
| GBCD3 | Cleveland | NYK |
| GBLVL | Cleveleys | BPL |
| GBCLF | Cliffe | KEN |
| GBCFT | Clifton | BST |
| GBCPT | Clipstone | CBF |
| GBCPS | Clipstone | NTT |
| GBCLI | Clitheroe | LAN |
| GBCGP | Cloghan Point/carrickfergus | CKF |
| GBGHR | Clogher | |
| GBCPM | Clopton | NTH |
| GBCUF | Cloughfold | LAN |
| GBCGM | Cloughmills | BLY |
| GBCVL | Clovelly | CON |