Here bus timings from Chennai to Madurai buses private buses:
NATIONAL TRAVELS CHN
Non A/C Seater/Sleeper (2+1)
21:15
06:00
Kallada Travels Suresh Kallada
Volvo A/C MultiAxle Semisleeper (2+2)
20:45
03:35
Parveen Travels
Mercedes Multi-Axle Semi-sleeper (2+2)
22:45
06:15
NATIONAL TRAVELS CHN
A/C Sleeper (2+1)
22:15
06:00
Shama Sardar Travels HPM
A/C Sleeper (2+1)
23:25
07:15
Universal TravelsUTS
Scania AC Multi Axle Semi Sleeper(2+2)
23:25
05:00
Thirumal Alaghu Travels
Scania AC Multi Axle Semi Sleeper(2+2)
21:25
03:30