The Josiah Cowles House stands on the south side of Marion Avenue, between Sunny Ridge Drive and Old Mill Road west of the village center of Plantsville and Interstate 84.

It is a 2+1⁄2-story wood-frame structure, five bays wide, with a side-gable roof, central chimney, and clapboarded exterior.

The door is framed by simple trim, while the windows are surmounted by slightly projecting caps.

[2] Although traditionally ascribed a construction date of 1728, the architecture suggests it was built closer to 1750, probably around the time of Josiah Cowles' second marriage.

[3] At the very first town meeting after the incorporation of Southington, held November 11, 1779, the residents appointed Cowles, along with Jonathan Root to a committee to "provide for the families of officers and soldiers in the field.