Seventy-five thousand Telstra customers across the country experienced network outages on Saturday.
Internet ADSL and NBN services were down in some areas of NSW, Victoria, Queensland, WA, SA and Tasmania.
Irritated Telstra customerstook to Twitter, withthe hashtag #telstraoutage trending.
The website Aussie Outages received hundreds of outage reports since about 11am on Saturday.
A Telstra spokesman said services had been progressively restored.
"From around midday to 4pm today, some of our broadband customers were unable to establish an internet connection," he said.
"Approximately 75,000 customers were directly affected.
"The issue has now been resolved and we apologise for any inconvenience."
There were several other outages reported earlier in the year. In February Telstra's chief operations officer Kate McKenzie said another widespread outage was caused by "human error".