For NATHAM to KOTTAIYUR TNSTC bus timings and Ticket Booking, please visit the official TNSTC Reservation Centre for the latest and reliable information on schedules, routes, and ticket prices Tamil Nadu operates this center, and you can also check as a traveler SETC online bus booking and obtain information on SETC bus timings and fares.
| Route | Source | Source Time | Destination | Destination Time | Class | STU |
| 551A | NATHAM | 11:35:00 | KOTTAIYUR | 12:25:00 | ORD | TNSTC-MDU |
| 551A | NATHAM | 16:35:00 | KOTTAIYUR | 17:25:00 | ORD | TNSTC-MDU |
| 551A | NATHAM | 20:30:00 | KOTTAIYUR | 21:25:00 | ORD | TNSTC-MDU |
| 551B | NATHAM | 6:30:00 | KOTTAIYUR | 7:15:00 | ORD | TNSTC-MDU |
| 551B | NATHAM | 8:25:00 | KOTTAIYUR | 9:15:00 | ORD | TNSTC-MDU |
| 551B | NATHAM | 10:00:00 | KOTTAIYUR | 10:55:00 | ORD | TNSTC-MDU |
| 551B | NATHAM | 13:10:00 | KOTTAIYUR | 13:55:00 | ORD | TNSTC-MDU |
| 551B | NATHAM | 15:00:00 | KOTTAIYUR | 15:45:00 | ORD | TNSTC-MDU |
| 551B | NATHAM | 17:25:00 | KOTTAIYUR | 18:20:00 | ORD | TNSTC-MDU |
| 551B | NATHAM | 19:25:00 | KOTTAIYUR | 20:20:00 | ORD | TNSTC-MDU |
| 552A | NATHAM | 9:15:00 | KOTTAIYUR | 10:05:00 | ORD | TNSTC-MDU |
| 552A | NATHAM | 12:15:00 | KOTTAIYUR | 13:00:00 | ORD | TNSTC-MDU |
| 552A | NATHAM | 15:15:00 | KOTTAIYUR | 16:10:00 | ORD | TNSTC-MDU |
| 555A | NATHAM | 5:45:00 | KOTTAIYUR | 6:45:00 | ORD | TNSTC-MDU |
| 556A | NATHAM | 20:05:00 | KOTTAIYUR | 20:50:00 | ORD | TNSTC-MDU |
| 557A | NATHAM | 18:15:00 | KOTTAIYUR | 21:00:00 | ORD | TNSTC-MDU |
