SYDNEY, March 30, 2026, 05:11 AEDT
- Optus and TPG have lined up against Telstra ahead of a March 31 ACMA decision on national mobile coverage-map rules. 1
- Telstra says the draft would force it to remove about 1 million square kilometres from areas it now marks as covered. 2
- Telstra argues 1.5 million customers a month still use service below the proposed threshold, including 57,000 emergency calls a year. 3
Telstra Group Limited is facing a fresh challenge to its long-used mobile coverage pitch after Optus and TPG lined up behind tougher map rules ahead of an Australian regulator’s ruling due by March 31. The proposed change could force Telstra to strip about 1 million square kilometres from areas it currently shows as served. 1
The timing matters. The Australian Communications and Media Authority must finalise its Mobile Network Coverage Maps Standard by March 31, and the new rules are due to take effect on June 30, forcing carriers to use a harmonised method for modelling and labelling 4G and 5G outdoor handheld coverage. 4
The Australian Competition and Consumer Commission has backed the tighter approach, saying current maps can be hard to compare and may not match what users actually receive, leaving buyers exposed to unsuitable services. That matters in a market where Telstra leads with 41% mobile share, ahead of Optus on 29% and TPG on 17%, according to the watchdog’s 2024-25 market report. 5
Under ACMA’s draft, areas below -115 dBm — a measure of radio signal strength — would not count as usable coverage. Telstra wants the cutoff lowered to -122 dBm, while Optus and TPG want the regulator to keep the higher floor. 2
Telstra has leaned hard on network reach in selling itself to regional customers. The carrier says its mobile network reaches about 3 million square kilometres and 99.7% of Australians, and it has told the regulator the draft would wipe roughly a third of that landmass from its map. 6
Shailin Sehgal, Telstra’s group executive for global networks and technology, said in comments published by the Australian Financial Review that TPG’s testing “is in no way representative of the experience of our customers using our network across the country.” In a company post earlier this month, he also wrote that “every month more than 1.5 million customers use our coverage below -115 dBm.” 1
Telstra says those lower-signal areas still handle about 57,000 emergency calls a year, along with 700,000 voice calls and 750,000 texts a day. The government’s National Audit of Mobile Coverage is one of the inputs ACMA says informed the draft threshold and its push for clearer comparisons between carriers. 3
TPG, which sells Vodafone-branded mobile services, has argued that maps should show places where ordinary phones can reliably make calls, not just register a faint signal. Optus backed the same -115 dBm floor in its submission, saying anything weaker would risk overstating reliable service to consumers. 2
Telstra goes into the fight from a position of financial strength. Reuters reported in February that the company beat first-half profit expectations, helped by mobile customer growth and higher plan prices, and expanded its buyback to as much as A$1.25 billion; eToro analyst Zavier Wong then called it “one of the most defensive names on the ASX.” 7
But the outcome could still shift before ACMA publishes its final rule on March 31. If the regulator keeps the draft broadly intact, Telstra would have to redraw maps as the standard starts on June 30, while the company says a hard cutoff could confuse regional users and blur where terrestrial coverage ends and satellite-to-mobile services begin. 4
Whatever the final wording, the rule change would go beyond cartography. It could reset how Telstra markets its network edge against Optus and TPG, and how smaller resellers using those networks tell customers where their phones are likely to work. 4
