MTC Chennai route numbers decoded — what the letters mean
TownBus Admin · 16 May 2026
· updated 9 Jun 2026
B, C, D, G, K, M, S — every MTC route prefix tells you something. Here's the map.
MTC route numbers aren't random. The letter prefix encodes the route's class and direction:
- No prefix (just digits): Ordinary service, all stops
- B: Branch service, shorter loop off a main route
- C: Cut service, partial route
- D: Deluxe — fewer stops, slight premium fare
- E / EX: Express, limited stops
- G: Grand route — long-distance Chennai service
- K: Koyambedu-anchored
- M: Madhavaram-anchored
- S: Special — short-trip last-mile loops
- AC prefix: air-conditioned
So 27B is a branch off the main 27. M70 runs from Madhavaram. K47C is a cut version of the K47 route.
Understanding the prefix lets you guess where a route goes even when you've never taken it.
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