They recline. Not sure exactly how to measure it, but it is about 4 1/2 inches at the top by your shoulders. The rear seat is 60/40 so the left side and center are the same back and recline together.
If you do travel with people back there you might want to option for the 7 seater. The 6 and 7 seat options have second A/C evaporator, ducting, and fan for the back seats, so have more cooling in the back than the 5 seater.