In Thiruvallur district, Tamil Nadu, PIN code 631211 is anchored by Karthikeyapuram B.O, a Branch Post Office. Mail addressed to this code is sorted through the Southern Postal Region, across 3 listed offices.
| Post office | Type | Full name |
|---|---|---|
| Karthikeyapuram B.O | BO | Branch Post Office |
| Saraswathinagar S.O | SO | Sub Post Office |
| Kasavarajpetta B.O | BO | Branch Post Office |
