Speight, 30, signed a one-year extension to remain in Australia until at least the end of the Rugby World Cup.
A veteran of 19 Tests, Speight was delighted to earn a longer stay, including with the Brumbies.
"There's still a lot to achieve with both the Brumbies and the Wallabies so I'm really excited to be staying in Canberra for another year," he said.
"The World Cup is a big target of mine. I really enjoyed the experience in 2015 but I want to go one step further next year so hopefully I'm part of that.