Telstra says it has fixed a major outage that hit calls and internet across Australia on Tuesday.

It follows reports from thousands of customers of issues with Telstra coverage.

“If you’re a Telstra customer you might be noticing some issues with mobile calls. We’re working on a fix and hope to get everything back up and running soon,” the company wrote on social media about 2pm.

“We’ll keep you updated.”

While the cause of the outage appeared to be a mystery, Telstra said mobile data was not affected. Nor were triple-zero calls.

“We’ll let you know once we have more info,” it wrote.

Telstra complaints showed a big spike early on Tuesday afternoon. Image: Downdetector

Website Down Detector, which monitors tech outages, showed a significant spike in issues with the telco about midday (AEDT).

“Tough trying to run a business with Telstra today. Can’t talk to anyone and lines constantly drop [out],” wrote one customer.

“Have had reports of people’s mobile calls experiencing dead air. Can’t hear the other party and they can’t hear the caller. Seems to be intermittent,” wrote another.

On social media, affected customers compared the issue to Optus’s nationwide outage last year.

“Come on Telstra! After the s–t storm with Optus last year. I thought you would’ve put in measures so this didn’t happen with you guys,” wrote on user.

Optus endured a major outage in November last year that left millions of Australians disconnected for close to nine hours.

Transport networks, health systems and the Australian Tax Office were all among those affected, while the company later admitted that hundreds of emergency phone calls had gone unanswered.

Telstra said shortly later on Tuesday afternoon that it had fixed the problem.

“Good news! The issue impacting some mobile voice calls was fixed at around 2.30PM (AEDT) today. The issue was caused by a software change. We’re sorry for the impact on your day,” it wrote on X.