After announcing his resignation in March, Andrew Penn capped off his years of service as CEO of Telstra by highlighting the support he received from his team.

"I know I asked a lot of the team during my tenure, but they stepped up every day to deliver, and I'm immensely proud to have been your leader during this time," Penn said in a message on social media.

"I'll be very sad to leave but also very proud of what we've achieved."

With more than three decades of experience in the C-Suite, Penn has been instrumental in the transformation initiatives of his organisations. The most recent one was the T22 strategy and the digitisation of services at Telstra.

"Today, it's a very different Telstra to the one I stepped in to lead seven years ago," he said. "The number of complaints has more than halved. We've improved the financial trajectory of the business and we're delivering some great technology solutions."

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Telstra's shift towards a digital-first experience purportedly lays down the foundation of the company's growth in the years to come.

"During his time as CEO, Andy has driven a focus on digitisation underpinned by a commitment to simplifying our products and services," Chairman John Mullen said of Penn.

Mullen added how the outgoing CEO exhibited leadership during an "extraordinary time" as the company navigated the challenges of the pandemic.

Upon Penn's departure, former CFO Vicki Brady will take over as chief executive – the first woman to do so in the history of Telstra. In 2016, Brady came on board at the telco as group executive for consumer and small business. She became finance chief three years later.

Mullen said Brady "played a key leadership role in the development of Telstra's T25 strategy and is well placed to lead the company through its next phase".