Telstra has been fined $A510,000 for failing to connect new landline customers on time.
AAP reports that under federal law, the company is required to connect new urban customers within two days, provided their property has an existing, working, telephone line.
The Australian Communications and Media Authority on Friday said Telstra successfully connected 88.6% of new connections during the 2012/13 financial year, which is below the authority's benchmark of 90%.
Chairman Chris Chapman said the fine took into account that the 2012/13 financial year was marked by a number of natural disasters and Telstra had since made a "significant effort" to improve its performance.
A Telstra spokesman said damage to the network from a string of natural disasters had impacted on the company's ability to connect new customers during 2012/13.
"Last (financial) year, we faced unprecedented damage to our network from natural disasters," he said in a statement.
"We fixed more than one million faults for our customers and a number of events, such as the Queensland floods, Tasmanian fires and Warrnambool Exchange fire, placed great strain on our network and resources across the country," he said.
He said Telstra accepted the ACMA finding and apologised to customers affected by the delays.