| Locality | Post Code |
|---|---|
| Cairndow, Argyll and Bute | PA26 |
| Calgary, Argyll and Bute | PA75 |
| Campbeltown, Argyll and Bute | PA28 |
| Caolila, Argyll and Bute | PA46 7RJ |
| Caolis, Argyll and Bute | PA77 |
| Cardross, Argyll and Bute | G82 |
| Carradale, Argyll and Bute | PA28 |
| Carradale East, Argyll and Bute | PA28 |
| Carrick Castle, Argyll and Bute | PA24 |
| Carse, Argyll and Bute | PA29 6YB |
| Castleton, Argyll and Bute | PA31 |
| Clachaig, Argyll and Bute | PA23 8RE |
| Clachan, Argyll and Bute | PA29 |
| Clachan Seil, Argyll and Bute | PA34 |
| Cladich, Argyll and Bute | PA33 1BQ |
| Clynder, Argyll and Bute | G84 |
| Colintraive, Argyll and Bute | PA22 |
| Connel, Argyll and Bute | PA37 |
| Cornaigbeg, Argyll and Bute | PA77 |
| Cornaigmore, Argyll and Bute | PA77 6XA |
| Cove, Argyll and Bute | G84 |
| Craighouse, Argyll and Bute | PA60 |
| Craignish, Argyll and Bute | PA31 8QS |
| Craignure, Argyll and Bute | PA65 |
| Craobh Haven, Argyll and Bute | PA31 |
| Crarae Furnace, Argyll and Bute | PA32 |