Chambers' inclusion in the world-class line-up came after thousands of fans petitioned Raggamuffin organisers via Facebook.
Chad has enjoyed a cult-like following since winning his heat of Homai Te Pakipaki, singing Bob Marley's Natural Mystic.
The second stage at the Saturday Raggamuffin festival will feature the winner of Pacifica Beats, Kiwi artists NRG Rising, Foundation, Soljah, Tomorrow People, Cornerstone Roots, House of Shem and international artists NKulee Dube.
McManus Entertainment - promoter of the reggae, hip-hop, dancehall, funk, dub and RnB event - has said Katchafire and Arrested Development would be entertaining the expected 30,000-strong crowd on both days of the festival.
Katchafire and Arrested Development will start the event by performing at the Mai FM Party on Friday night then again on the main stage on Saturday.
Other Kiwi artists joining them on the Friday night stage include DJ Sir-Vere, Sons of Zion and Sweet and Irie.
Next year will be the third year Arrested Development has been part of the Raggamuffin line-up in Rotorua and the second for Sly and Robbie, who performed at this year's festival at the Rotorua International Stadium.
J-Boog, who will experience his first Raggamuffin as a performer next year, has dominated airwaves with his hit Let's Do It Again, which featured on the New Zealand Top 40 singles chart.