The Transport Agency expects the new give way rules will reduce crashes at intersections.
From 5am on Sunday, vehicles turning right will have to give way to vehicles from the opposite direction turning left.
Drivers at the bottom of T-intersections will give way to all traffic turning off the main road.
Transport Agency spokesperson Andy Knackstedt says the changes are expected to reduce crashes at intersections by about 7%, preventing 100 injuries and one fatality each year.
He says there is a crash at an intersection every 30 minutes, on average.
While there will be collisions at intersections on Sunday, he says, not all will be caused by the new rule change.
Mr Knackstedt says official data recorded on the crashes will show to what degree the changes are reducing accidents.
