The team from Gqeberha can add another SA20 trophy to the cabinet when they take on Pretoria Capitals in the final at Newlands on Sunday.
The Sunrisers have won the title in two of the previous three seasons while they were also losing finalists in the tournament last time out.
The Royals had won the toss and opted to bat in the knockout contest but only managed to reach a total of 114-7 in their 20 overs on a Wanderers pitch that aided the spinners.
Proteas left-arm tweaker Senuran Muthusamy had a brilliant day out with figures of 3-15 in his four overs while English spinner James Coles continued to show his mettle with 1-15.
Kyle Verreynne opened the batting for the team from Paarl and held it together for the entire innings to be 52 not out from 42 balls on a surface that was difficult to score quickly.
The Royals were pegged back and lost wickets at regular intervals but Proteas gloveman Verreynne stood firm to at least give his team something to bowl at.
The Sunrisers were intent on a quick start in the run-chase to dispel any nervousness and Quinton de Kock gave them that, slapping three fours and two sixes in a quick-fire 25 off 12 balls.
Royals spinner Bjorn Fortuin, however, threw a spanner in the works, dismissing De Kock and Jonny Bairstow in the third over.
When Ottneil Baartman had Jordan Hermann (17) caught at mid-on the Sunrisers slipped to 50-3 and the Roylas might have started to believe again.
Coles though came out and smashed an unbeaten 45 off just 19 deliveries and, together with Matthew Breetzke (19 not out), took the Sunrisers over the line in the 12th over.