Reliance Jio, India's largest service provider, lost 19 million subscribers in September and saw its market share dip from 37% in August to 36.43%, according to the latest data released by the Telecom Authority of India (TRAI).

At the end of September, Jio had 424 million subscribers, down from 443 million in August. In comparison, Bharti Airtel added about 270,000 subscribers in September, while Vodafone Idea lost 1 million.

This drop in subscriber numbers for Jio seems to be a continuation of the trend seen earlier this year, when Jio lost 11 million subscribers in the second quarter.

"During the peak of the second wave [of COVID-19, during the April-to-May timeframe], we had done a lot of initiatives … giving free voice minutes to keep them on our network," said Kiran Thomas, Reliance Jio's president, on the last earnings call.

"But two quarters later, we find that a large number of people at the bottom of the pyramid have not been able to stay up-to-date with recharges," he continued.

That said, only 6.6 million of the 19 million subscribers that Jio lost in the September-ending quarter live in poorer rural communities.

Jio's database has continued to feature a high number of inactive subscribers who are typically removed after 90 days. It is commonly used as a second SIM throughout India, which helps to explain the losses that occurred outside rural India.

But the loss of inactive subscribers, coupled with growing data consumption, should help Jio to boost average revenue per user (ARPU). That figure rose from 138 Indian rupees ($1.38) between April and June quarter to INR144 ($1.93) in the September-ending quarter.

The story of inactive subscribers

The low tariffs at Jio's launch persuaded many consumers to adopt Jio as a second SIM, a phenomenon that continued even when Jio launched its JioPhone in 2019.

It is one of the key reasons Jio continues to have a lower number of active subscribers on its network than its rivals claim. Airtel says 97.86% of its users are active, while Vodafone Idea's rate is 87.31%. At Jio, only 83.65% of subscribers are classed as active.

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Another reason for Jio's high number of inactive subscribers is the company's policy of not terminating service even after plans expire. Users can continue to receive incoming calls even when they have not recharged. This is not the case with Airtel and Vodafone Idea.

Jio may be hoping the recently launched JioPhone Next, an affordable smartphone, will help to boost the number of active subscribers on its network.

— Gagandeep Kaur, contributing editor, special to Light Reading