RBAI made it 14 wins in the Schools' Cup, completing a hat-trick of wins in their fifth consecutive final.
The victory was set up by an impressive display from their bowling unit that bundled Sullivan Upper out for 88 - Reuben Shine making 13.
Daniel Henry took the plaudits with four wickets, closely followed by James West with three, Adam Leckey with two, and Ben Craigan one.
The modest target was knocked off in 10.1 overs with George Craigan hitting four sixes and fours in an unbeaten 52, sharing an opening stand of 92 with James West (26*).
“It’s a really remarkable achievement,” said Darren O’Neill Head of Cricket at RBAI.
NCU President Bryan Milford with RBAI captain Adam Leckey
“Thanks must go to Jonny Peake, Head Coach, and of course the team who have been fantastic all year. A really talented team from 1 to 11. And for the Upper sixth guys, it's a great way to finish their seven years at Inst.”
And going now for four-in-row?
"Yes, why not. We target it every year, and it's a great competition. We love playing in it, the longer form of the game. We have a good crop of boys coming through and that will be the aim."