We present a search for extreme emission line galaxies (EELGs) at z<1 in the COSMOS and North Ecliptic Pole (NEP) fields with imaging from Subaru/Hyper Suprime-Cam (HSC) and a combination of new and existing spectroscopy. We select EELGs on the basis of substantial excess flux in the z broadband, which is sensitive to H$\alpha$ at 0.3Comment: Accepted for publication in ApJ. 18 pages, 10 Figures, 2 Tables