Row houses in cold climates with increased shared wall for energy efficiency, suffer from darker interior spaces. Addition of courtyards can solve this problem to some extent, but courtyards are responsible for higher energy consumption during winter. This study investigates an alternative option, i.e. converting courtyard into atrium during winter for assessing its energy and daylight performance in row houses in Toronto. Results are determined by using Design Builder software. Research shows, during winter atrium options in row houses can reduce energy consumption compared to courtyard, but at the same time daylit floor area above target illuminance is also reduced. However, bigger courtyard having large window to wall ratio, clear glazing for courtyard windows and low e coated glazing for skylight can create a balance between increased energy consumption and decreased daylighting inside the house to maximize the benefits from converting courtyard into atrium during winter in Toronto row houses.