In a statement on Wednesday, the ACMA said it had found that these telcos had provided incorrect information, or failed to provide any data, to the Integrated Public Number Database which has about 72 million connected numbers.

A majority of the violations were by Telstra, Singtel Optus and Vodafone Hutchison Australia.

"While the ACMA is not aware of any specific instances of harm caused by the missing or inaccurate information, the scale of the issue and its potential impact on emergency services is very concerning," said ACMA chair Nerida O’Loughlin.

The offending telcos have been told to audit their processes, conduct data reconciliations and comply with the IPND code.

Additionally, Optus, Telstra and Symbio have been ordered to address outstanding missing and inaccurate records.

"We’ll be looking very closely at the reconciliations and independent audit results and will consider further action if needed," added O’Loughlin.

Penalties of up to $10 million can be levied on telcos who fail to comply with the remedial directions, and they can be fined up to $250,000 for the directions to comply.