The cost of an extra bedroom can vary significantly. In some cases, it may increase the estimated monthly housing payment by just $16. However, in other instances, the added cost can exceed $20,000 per month.

A recent analysis compared median list prices for homes with different numbers of bedrooms in various markets. The study used data from over 1 million active single-family listings across 255 US cities. It translated price differences into estimated monthly mortgage payments, taking into account factors like property taxes and homeowners insurance.

Nationally, adding a third bedroom to a two-bedroom home is estimated to increase the monthly housing payment by around $648. Further details on the analysis are available from the source.