Abstract: A window well assembly includes U-shaped walls that have smooth interior and corrugated exterior surfaces, and are formed from polyvinyl material. The walls have coextensive ribs juxtaposed along an exterior surface thereof that are compressible. Each wall has an end wall with an opening formed therein, allowing the ribs to compress and expand. The openings are spaced at opposed ends of selected ribs. A mechanism is included for stacking the walls wherein a top edge of one wall receives a bottom edge of another wall. Ladders are seated against the interior surfaces of the walls. A mechanism is included for snapping the ladders onto the wall interior surface. A safety grill is mounted on top of the second wall, having an outer edge extending along a top edge of the second wall, for prohibiting the user from stepping into a cavity defined between the walls and the foundation window wall.