| Place | Post Code |
|---|---|
| Idaikorai, Thiruvaiyaru | 613205 |
| Kachamangalam, Thiruvaiyaru | 613102 |
| Kadanbangudi, Thiruvaiyaru | 613101 |
| Kaduvelli, Thiruvaiyaru | 613203 |
| Kakkaiyadi, Thiruvaiyaru | 613203 |
| Kalarpatti, Thiruvaiyaru | 613602 |
| Kalayanapuram, Thiruvaiyaru | 613201 |
| Kalayanapuram I Sethi, Thiruvaiyaru | 613202 |
| Kallakudi, Thiruvaiyaru | 613204 |
| Kalumangalam, Thiruvaiyaru | 613602 |
| Kalyanapuram II Sethi, Thiruvaiyaru | 613202 |
| Kalybanurajathottam, Thiruvaiyaru | 613205 |
| Kambur, Thiruvaiyaru | 613203 |
| Kanakkanar Gudi, Thiruvaiyaru | 613205 |
| Kandamangalam, Thiruvaiyaru | 613104 |
| Kandiyur, Thiruvaiyaru | 613202 |
| Karkudi, Thiruvaiyaru | 613204 |
| Karuppur, Thiruvaiyaru | 613101 |
| Karur, Thiruvaiyaru | 613205 |
| Kattukottai, Thiruvaiyaru | 613205 |
| Keela Sathanur, Thiruvaiyaru | 613203 |
| Keelakaruppur, Thiruvaiyaru | 613101 |
| Keelamaharajapuram, Thiruvaiyaru | 613203 |
| Keezha Puna Vasal, Thiruvaiyaru | 613204 |
| Kilathirupanthuruthi, Thiruvaiyaru | 613103 |
| Kilathiruppanthuruthi, Thiruvaiyaru | 613103 |