The club is also expected to table a new offer for Jacob Lillyman, though the future of fellow props Charlie Gubb and Albert Vete remain uncertain.
The 24-year-old Sao was a Warriors junior, but was unwanted at Mt Smart after the 2012 NYC season.
He joined the Manly Sea Eagles, following fellow former Warriors Peta Hiku to the north Sydney club.
After making his first grade debut in 2013, Sao's breakthrough came the following season, when he played 20 matches under Geoff Toovey.
The 1.87m, 110kg Sao came into the team in round four this year and has been an ever-present since then.
He's not the biggest forward, nor the strongest, but coach Stephen Kearney values his work ethic.
The former Manurewa Marlins junior also brings some added mongrel to the Warriors forwards, with his uncompromising approach.