ACCC chair Rod Sims said the commission was extremely conscious of the fact that mobile coverage and choice of service provider in regional, rural and remote areas are vital issues.
"However, the effect allowing roaming would have on competition in regional, rural and remote areas is uncertain. While it may deliver choice for more consumers, declaration has the potential to make some consumers worse off," Sims said.
"The ACCC has examined the incentives for mobile network operators to upgrade their networks or invest in expanding coverage both with and without roaming. We heard from many regional groups concerned about coverage. We consider there is evidence that roaming could damage some incentives for operators to invest," he said.
The Australian Communications Consumer Action Network (ACCAN), the peak body representing consumers in the telecommunications industry, said it welcomed the ACCC decision.
ACCAN CEO, Teresa Corbin said the consumer advocate questioned whether regulated domestic roaming would result in better mobile coverage and improved competition in regional, rural and remote areas.
"Consumers and small businesses in regional, rural and remote areas want additional coverage where they live, work and travel. It's unclear whether declaring domestic mobile roaming would achieve this," Corbin said.
"Improving and extending mobile coverage in regional and rural areas needs to be a priority for the Government and the mobile network operators. We call on the Federal Government to commit to funding further rounds of the Mobile Black Spot Program to extend coverage much further," she said.
NSW Farmers' president, Derek Schoen, said the farming advocate was pleased that the ACCC had recognised the importance of regional and rural customers in making its decision.
"Even with the current Mobile Black Spot Program, there are still large sections of regional NSW that are without mobile coverage," Schoen said.
We have been concerned that the coverage map is not filling in fast enough," he said.
"If the ACCC confirms this decision, we will be continuing to pressure the telecommunications companies to provide extended coverage to our members in rural and remote NSW, but also better, more competitive service."
"The onus is now on those who pushed for this result to demonstrate increased investment in coverage and service provision in the bush."
The ACCC said while it did not think mandated roaming was the answer to regional problems in regional and rural areas, it was seeking comment on other regulatory and policy measures that could improve coverage and competitive outcomes.