A window air conditioner, as the term suggests, is mounted on a window, whereas a split air conditioner can be mounted anywhere with no special requirements.

There is no difference in the efficiency of a window and a split air conditioner unit. The running cost is almost the same for both air conditioners. However, the power consumption in a split air conditioner is slightly higher when compared to a window air conditioner. In other words, the installation cost of a split air conditioner is low, but the ongoing cost is slightly higher.

For a window air conditioner, sometimes you need to use your existing window so that your window air conditioner fits there. However, since split air conditioners can be placed on the wall there is no need to have a window in the room.

The condensing unit of the split air conditioner is kept outside. Since the noisy part is kept out of the room, the noise levels remain low when compared to a window unit.