According To Telecom's

 Bharti Airtel: Delhi,Mumbai,Andhra pradesh,Karnataka,North East,Uttar pradesh(west),Rajasthan,West    bengal,Himachal pradesh,Bihar,Assam,Jammu and Kashmir,Tamilnadu,

  

Tata Docomo:Maharashtra,Gujrat,Karnataka,Kerala,Punjab,Haryana,Rajasthan,Uttarpradesh(west)      

                             Madhya pradesh,

Vodafone:Delhi,Mumbai,Maharashtra,Gujrat,Tamilnadu,Kolkata,Haryana,Uttar                                  pradesh(east),Westbengal

Reliance: Delhi,Mumbai,Kolkata,Punjab,Rajasthan,Madhya pradesh,North East,West bengal,Bihar,Himachal pradesh,Assam,Orissa,Jammu and Kashmir

Idea: Maharashtra,Gujrat,Andhra pradesh,Kerala,Punjab,Harayana,Uttar pradesh,Madhya pradesh,Himachal pradesh,Jammu and Kashmir

Delhi-->Vodafone , Bharti and Reliance

Mumbai-->Reliance , Vodafone , Bharti

Maharashtra-->Tata,Idea,Vodafone

Madhya Pradesh-->Idea,Reliance,Tata

Gujarat-->Tata,Idea,Vodafone

Andhra Pradesh-->Bharti,Idea,Aircel

Karnataka-->Tata,Aircel,Bharti

Tamil Nadu-->Bharti,Vodafone,Aircel

Kolkata-->Vodafone,Aircel,Reliance

Kerala-->Idea,Tata,Aircel

Punjab-->Idea,Reliance,Tata,Aircel

Haryana-->Idea,Tata,Vodafone

UP(East)-->Aircel,Idea,Vodafone

UP(West)-->Bharti,Idea,Tata

Rajasthan-->Reliance,Bharti,Tata

West Bengal-->Bharti,Reliance,Vodafone,Aircel

Himachal Pradesh-->Bharti,STel,Idea,Reliance

Bihar-->STel,Bharti,Reliance,Aircel

Orissa-->STel,Aircel,Reliance

Assam-->Reliance,Bharti,Aircel

North East-->Aircel,Bharti,Reliance

Jammu and Kashmir-->Idea,Aircel,Reliance,Bharti