| Cadgwith | (SW7214) | Cornwall | England | |
| Caistor | (TA1101) | Lincolnshire | England | |
| Calbourne | (SZ4286) | Hampshire and the Isle of Wight | England | |
| Caldecott | (SP8693) | Rutland | England | |
| Caldonlow | (SK0848) | Staffordshire | England | |
| Calne | (ST9971) | Wiltshire | England | |
| Calverton | (SK6149) | Nottinghamshire | England | |
| Cam | (ST7599) | Gloucestershire | England | |
| Cambo | (NZ0285) | Northumberland | England | |
| Camborne | (SW6440) | Cornwall | England | |
| Camely | (ST6057) | Somerset | England | |
| Campden, Chipping | (SP1539) | Gloucestershire | England | |
| Canes, Norton | (SK0107) | Staffordshire | England | |
| Caney Creek | (37.33463, -82.87549) | Kentucky | United States of America | |
| Cannings, All | (SU0761) | Wiltshire | England | |
| Cannock | (SJ9710) | Staffordshire | England | |
| Cark | (SD3676) | Lancashire | England | |
| Carlton | (SE6423) | Yorkshire - West Riding | England | |
| Carlton le Moorland | (SK9058) | Lincolnshire | England | |
| Carlton, North | (SK9477) | Lincolnshire | England | |
| Carlton, South | (SK9576) | Lincolnshire | England | |
| Carnalea | (J4781) | Down | Ireland | |
| Carndonagh | (C4745) | Donegal | Ireland | |
| Carnlough | (D2817) | Antrim | Ireland | |
| Carrickfergus | (J4187) | Antrim | Ireland | |
| Cartmel | (SD3778) | Lancashire | England | |
| Cary, Castle | (ST6332) | Somerset | England | |
| Castle Cary | (ST6332) | Somerset | England | |
| Castle, Barnard | (NZ0516) | Durham | England | |
| Castle, Belvoir | (SK8233) | Leicestershire | England | |
| Castle, Naworth | (NY5662) | Cumberland | England | |
| Castle, White | (C5232) | Donegal | Ireland | |
| Castlebar | (M1490) | Mayo | Ireland | |
| Castledawson | (H9293) | Londonderry | Ireland | |
| Castlederg | (H2684) | Tyrone | Ireland | |
| Castleton | (SK1582) | Derbyshire | England | |
| Castletown | (S7175) | Carlow | Ireland | |
| Castletown | (SC2667) | Isle of Man | Isle of Man | |
| Castlewellan | (J3436) | Down | Ireland | |
| Castor | (TL1298) | Northamptonshire and the Soke of Peterborough | England | |
| Catterick | (SE2397) | Yorkshire - North Riding | England | |
| Caunton | (SK7460) | Nottinghamshire | England | |
| Cerney, North | (SP0208) | Gloucestershire | England | |
| Cerney, South | (SU0497) | Gloucestershire | England | |
| Chaddleworth | (SU4177) | Berkshire | England | |
| Chadlington | (SP3221) | Oxfordshire | England | |
| Chadsmoor | (SJ9811) | Staffordshire | England | |
| Chale | (SZ4877) | Hampshire and the Isle of Wight | England | |
| Chalfont St. Giles | (SU9993) | Buckinghamshire | England | |
| Chalfont St. Peter | (SU9990) | Buckinghamshire | England | |
| Chalford | (SO8902) | Gloucestershire | England | |
| Chamber, Old | (SD9926) | Yorkshire - West Riding | England | |
| Change Islands | (49.67333, -54.41778) | Newfoundland | Canada | |
| Chapel Stile | (NY3205) | Westmorland | England | |
| Charlton-on-Otmoor | (SP5615) | Oxfordshire | England | |
| Chasetown | (SK0408) | Staffordshire | England | |
| Chawton | (SU7037) | Hampshire and the Isle of Wight | England | |
| Cheadle | (SK0043) | Staffordshire | England | |
| Checkendon | (SU6682) | Oxfordshire | England | |
| Chedworth | (SP0511) | Gloucestershire | England | |
| Chepstow | (ST5393) | Monmouthshire | Wales | |
| Cherington | (ST9098) | Gloucestershire | England | |
| Chesterfield | (SK3871) | Derbyshire | England | |
| Chidham | (SU7803) | Sussex | England | |
| Chieveley | (SU4773) | Berkshire | England | |
| Childrey | (SU3687) | Berkshire | England | |
| Chilton Foliat | (SU3270) | Wiltshire | England | |
| Chimney | (SP3500) | Oxfordshire | England | |
| Chipping Campden | (SP1539) | Gloucestershire | England | |
| Chipping Norton | (SP3127) | Oxfordshire | England | |
| Chiswick | (TQ2077) | Middlesex | England | |
| Chithurst | (SU8423) | Sussex | England | |
| Cholsey | (SU5886) | Berkshire | England | |
| Chopwell | (NZ1258) | Durham | England | |
| Chorlton cum Hardy | (SJ8193) | Lancashire | England | |
| Church Broughton | (SK2033) | Derbyshire | England | |
| Church Enstone | (SP3825) | Oxfordshire | England | |
| Churchover | (SP5080) | Warwickshire | England | |
| Churchtown | (T1205) | Wexford | Ireland | |
| Churt | (SU8538) | Surrey | England | |
| Cinderford | (SO6513) | Gloucestershire | England | |
| Clarebrand | (NX7666) | Kircudbrightshire | Scotland | |
| Claydon, Steeple | (SP7026) | Buckinghamshire | England | |
| Claypole | (SK8549) | Lincolnshire | England | |
| Clayton | (SE4507) | Yorkshire - West Riding | England | |
| Clayworth | (SK7288) | Nottinghamshire | England | |
| Cleeve Prior | (SP0849) | Worcestershire | England | |
| Clifford | (SE4244) | Yorkshire - West Riding | England | |
| Clifton | (SK5434) | Nottinghamshire | England | |
| Clipsham | (SK9616) | Rutland | England | |
| Clogher Dist. | (H5-5-) | Tyrone | Ireland | |
| Clones | (H5025) | Monaghan | Ireland | |
| Clowne | (SK4975) | Derbyshire | England | |
| Clunbury | (SO3780) | Shropshire | England | |
| Clyst, Broad | (SX9897) | Devonshire | England | |
| Coal Aston | (SK3679) | Derbyshire | England | |
| Coates | (SO9700) | Gloucestershire | England | |
| Cockerham | (SD4651) | Lancashire | England | |
| Cocking | (SU8717) | Sussex | England | |
| Coin St Aldwyn | (SP1405) | Gloucestershire | England | |
| Coleford | (SO5710) | Gloucestershire | England | |
| Coleraine | (C8532) | Antrim | Ireland | |
| Colliery, Ludworth | (NZ3641) | Durham | England | |
| Collingham | (SK8362) | Nottinghamshire | England | |
| Collingham, North | (SK8362) | Nottinghamshire | England | |
| Collyweston | (SK9902) | Northamptonshire and the Soke of Peterborough | England | |
| Colsterworth | (SK9324) | Lincolnshire | England | |
| Comberbach | (SJ6477) | Cheshire | England | |
| Commons, Bargy | (S9716) | Wexford | Ireland | |
| Commons, Forth | (S9817) | Wexford | Ireland | |
| Compton | (SU5279) | Berkshire | England | |
| Compton | (SU7714) | Sussex | England | |
| Compton, Little | (SP2630) | Warwickshire | England | |
| Congleton | (SJ8562) | Cheshire | England | |
| Coningsby | (TF2258) | Lincolnshire | England | |
| Connor Downs | (SW5939) | Cornwall | England | |
| Consett | (NZ1050) | Durham | England | |
| Convoy | (C2101) | Donegal | Ireland | |
| Cookham Dean | (SU8785) | Berkshire | England | |
| Cooneen | (H4542) | Fermanagh | Ireland | |
| Cork | (W6772) | Cork | Ireland | |
| Cornascreeb | (H9947) | Armagh | Ireland | |
| Cotgrave | (SK6435) | Nottinghamshire | England | |
| Cottesmore | (SK9013) | Rutland | England | |
| Country, Border | [Unlocated] | Scotland | ||
| Courtenay, Sutton | (SU5093) | Berkshire | England | |
| Cowes, East | (SZ5095) | Hampshire and the Isle of Wight | England | |
| Coxbench | (SK3743) | Derbyshire | England | |
| Coxwold | (SE5377) | Yorkshire - North Riding | England | |
| Cradley Heath | (SO9486) | Staffordshire | England | |
| Craigboy | (J5877) | Down | Ireland | |
| Cranborne | (SU0513) | Dorset | England | |
| Cranbrooke | (H4347) | Fermanagh | Ireland | |
| Cranswick | (TA0252) | Yorkshire - East Riding | England | |
| Cranswick, Hutton | (TA0252) | Yorkshire - East Riding | England | |
| Crebilly | (D1303) | Antrim | Ireland | |
| Creek, Caney | (37.33463, -82.87549) | Kentucky | United States of America | |
| Creeslough | (C0630) | Donegal | Ireland | |
| Crendon, Long | (SP6908) | Buckinghamshire | England | |
| Cricklade | (SU0993) | Wiltshire | England | |
| Crieff | (NN8621) | Perthshire | Scotland | |
| Crondall | (SU7948) | Hampshire and the Isle of Wight | England | |
| Crookham | (SU7952) | Hampshire and the Isle of Wight | England | |
| Crookham Street | (SU8052) | Hampshire and the Isle of Wight | England | |
| Cropwell | (SK6836) | Nottinghamshire | England | |
| Cropwell Bishop | (SK6835) | Nottinghamshire | England | |
| Cropwell Butler | (SK6837) | Nottinghamshire | England | |
| Crosby | (SE8811) | Lincolnshire | England | |
| Crosland Moor | (SE1114) | Yorkshire - West Riding | England | |
| Cross, King | (SE0724) | Yorkshire - West Riding | England | |
| Crossmaglen | (H9115) | Armagh | Ireland | |
| Crowhurst | (TQ7512) | Sussex | England | |
| Croxleygreen | (TQ0795) | Hertfordshire | England | |
| Croxton Kerrial | (SK8329) | Leicestershire | England | |
| Cuckney | (SK5671) | Nottinghamshire | England | |
| Cuddesdon | (SP5902) | Oxfordshire | England | |
| Culham | (SU5095) | Oxfordshire | England | |
| Cumcatch | (NY5461) | Cumberland | England | |
| Cumnock | (NS5620) | Ayrshire | Scotland | |
| Cumnor | (SP4604) | Berkshire | England | |
| Curbridge | (SP3308) | Oxfordshire | England | |
| Curracloe | (T0927) | Wexford | Ireland | |
| Curtis, Thornton | (TA0817) | Lincolnshire | England | |
| Cutthorpe | (SK3473) | Derbyshire | England |