A basement egress window installation costs between $500 and $1,000. There are several factors to consider when determining the cost, including the size, the material, and whether or not you need a contractor to install it. The cost of egress windows installation largely depends on the type of egress window which has to be installed. In general, basement windows come in four types: Casement doors, fixed doors, double-hung doors, and slider doors; all cost differently according to their size and style. More oversized windows cost more. Likewise, the styling also increases cost.