The job cuts could lead to the company shedding up to nine per cent of its 30,000-strong workforce by the end of 2024 and contribute to savings of $350 million at the firm, which is among the nation's largest by market value.
Talks with workers and unions on initial cuts to nearly 400 jobs would start immediately, the company said in an update to the share market on Tuesday.
The axed roles would mainly come from a "reset" of the telco's business-to-business enterprise division, including roles in tech services, consulting, sales and delivery teams.
Telstra would simplify its enterprise offering after expanding too far from its core services, chief executive Vicki Brady told reporters in Sydney.
"While parts of our business are performing strongly, there are parts that are not delivering to expectation," she said.
"These changes to our product set are focused on big businesses and big organisations, and again, we will work with our customers as we transition them to a more modern set of products."
Telstra Purple, a consulting business aimed at helping other firms in the shift to digital technology, will be the primary operation affected by the changes.
Telstra might partner with former competitors to take on its customers while the telco streamlined its operations, Ms Brady said.
The business needed to be sustainable to keep investing enough to meet ever-increasing connectivity and data demands, she said.
"I am confident we will come out the other side of this a more focused and successful company," she said.
Telstra CEO Vicki Brady says the restructure and redundancies could cost up to $250 million. (Bianca De Marchi/AAP PHOTOS)
While bad news for thousands of Telstra workers, the company offered some balm for consumers as it announced that mobile customers would be spared an increase in prices for post-paid plans that would ordinarily occur in July.
Telstra was removing the annual pricing review linked to the consumer price index on those plans, but it was still deciding how it would set prices in the future, Ms Brady said.
It will also "reshape some of its internal operations" by shifting staff from its global business services into other parts of the company.
The announcement came within "an evolving competitive landscape, rapid advances in technology, changing customer needs and ongoing inflationary pressures", Telstra told the share market.
Potential redundancies were flagged in February when the company revealed about $105 million, or 20 per cent, of savings outlined in its long-term strategy had been achieved.
The restructure and redundancies could cost up to $250 million, but Ms Brady said supporting workers was her highest priority.
Telstra's redundancy provisions were industry leading and the company would help workers gain skills as they transitioned into new roles, she said.
Most of the 2800 jobs will be axed by the end of 2024. (Bianca De Marchi/AAP PHOTOS)
The Communication Workers Union said the announcement came out of the blue and thousands of workers had woken up to the news their jobs were at risk.
"Workers are already facing the brunt of cost-of-living pressures and now they're having to contend with attacks on their jobs," national assistant secretary James Perkins said.
Treasurer Jim Chalmers said the job cuts would come as distressing news to a lot of people and his thoughts were with all of the families affected.
"We need to make sure that services don't suffer as a consequence of these changes," he said.
Telstra reported an increase in half-yearly income and profits in February on the back of strong growth in its mobiles business.
Its share price was down more than 2.1 per cent at midday on Tuesday as investors digested the announcement.