Cost Factors. Replacing a window costs an average of $300 to $700 per window. This assumes that the replacement window is going into an existing and structurally sound frame on a ground floor. Replacing windows in a typical three-bedroom, single-story home with ten windows can cost from $3,000 to $7,000.This cost can easily double for a two-story home.In the case that a window frame must be replaced, it is called a new construction window. A new construction window can increase the cost of replacement by as much as 50% to 100%, raising the average cost to anywhere from $5,000 to $40,000.his assumes that the replacement window is going into an existing and structurally sound frame on a ground floor. Replacing windows in a typical three-bedroom, single-story home with ten windows can cost from $3,000 to $7,000. This cost can easily double for a two-story home.