Abstract: The present invention is an outlet cover that is useful for covering a cylindrical socket type outlet. The outlet cover provides a watertight cover that is useful in marine applications and may be useful in automotive applications as well. The outlet cover has a base that has a flange. An upstanding ring extends upwardly from the base and an annular notch that has a diameter smaller than the outer diameter of the upstanding ring. A cap has a tether that joins the base to the cap. An annular rib in the cap is adapted for mating with the annular notch on the base. The annular rib includes a notch partially through it and is adapted for accommodating the tether when the annular rib is mated with the notch on the base.