Delhi and NCR markets contribute over three million subscribers to the total user base of 10 million in the northern hub, the company said in a statement.
In April to March period, it added 11.58 lakh subscribers in the region.
"We will strengthen our presence across the north hub and our focus will always remain on providing superior communication experience to our customers," Tata Teleservices Circle Operating Officer (Delhi and NCR), Vineet Bhatia said.