Lighting or illumination is the deliberate use of light to achieve a practical or aesthetic effect. All Animal Crossing series games have furniture that emits light, and some have included the feature to operate a light switch which works independently to any furniture in a player's house. The day-night cycle will also have an effect on a room if it contains windows.

In New Leaf, the lighting system has been drastically improved. Different lights and lamps emit different colors, and stack with others. Lights that have been refurbished by Cyrus will emit different light depending on their new color. The lighting in the main room of the player's home will affect the door's lighting from the outside. The base light colors include blue, green, indigo, orange, peach, pink, purple, red, white and yellow. The maximum light level for a stacked single color is 3. Custom designs on lamps will have an effect on the light output depending on the dominant design color.