Curran has effectively replaced all-rounder John Hastings, who retired from competitive cricket earlier this year.
The 23-year-old Curran join fellow England international Joe Denly at the Sixers.
“I’m absolutely delighted to be joining the Sydney Sixers for the 2018-19 Big Bash. Friends and colleagues have told me what a great team environment it is and how passionate the fans are and I’m hugely excited to experience this all for myself,” he said.
“I can’t wait to get to Sydney and hopefully help the team have a great season.”
Curran has played two Tests, 11 ODIs and seven T20Is – an recently represented the Kerala Knights in Sharjah’s T10 League. He also boasts experience for the Kolkata Knight Riders in the Indian Premier League.
Check out this great Big Bash prediction. for the 18/19 season!