HD 18599 is an orange K-type dwarf (about 0.86 solar masses, 5,145 K, 0.77 solar radii), 38.6 light-years from Earth. HD 18599 b is a 0.08-Jupiter-mass companion, with an orbital period of 4.1 days, at 0.048 AU from its star, on an eccentric orbit (e ≈ 0.34), discovered in 2022 via transit. The planet was found when it crossed the face of its star, producing periodic dips in brightness that reveal its size and orbital period to space-based photometry. The planet's marked eccentricity suggests past scattering events or perturbations from unseen companions.