A house number illumination device for lighting a house number on a mailbox includes a housing that defines an interior space. A power module is coupled to the housing and positioned in the interior space. Each of a plurality of fixtures is operationally coupled to the power module by a respective wire that extends from the housing. Each fixture is configured to couple to a surface proximate to a respective digit of a house number. Each fixture comprises a bulb so that the plurality of fixtures is configured to illuminate the house number.