After approval from Competition Commission of India (CCI) to merge consumer mobile businesses of Tata Teleservices Limited and Tata Teleservices Maharashtra Limited into Bharti Airtel a week ago, the telco said that Tata customers will now start transitioning to the Airtel mobile network under an Intra Circle Roaming (ICR) arrangement.

The first batch of the transition starts with UP (West), Bihar, and West Bengal. Over the coming weeks, all consumer mobile customers of Tata Teleservices across all circles will gradually transition to the Airtel network. The Tata Teleservices customers will be able to continue using the same SIM, as well as same plans/pack benefits they are using currently. The company said in a statement that there will be no disruption in the services during the transition.

As of March 31, 2017, TTML had 551,983 wireline subscribers and 2.59 million mobile subscribers in the Mumbai circle, and 309,408 wireline subscribers and 4.68 million mobile subscribers in the Maharashtra circle. These will be an addition to Airtel’s 281 million mobile connections (as of August 2017). Read more about Bharti Airtel and the Tata Group deal here.