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The Ion Velocity Meter (IVM) on NASA's Ionospheric Connection Explorer (ICON) reports the in-situ ion density, ion temperature and 3-component ion drift velocity, retrieved from the measurement by a retarding potential analyzer and an ion drift meter. The uncertainty of the drift velocity is known to be influenced by the ion density and O+ fraction, according to the pre-flight performance test. ICON was launched into a deep solar minimum in late 2019, followed by a solar quiet (F10. 7< 80) period until September 2020. To quantify the uncertainty of the IVM's drift velocity in the low plasma density environment, the cross-comparisons among equatorial electric field (EEF) as obtained from Swarm's electrojet (EEJ) current measurements, the vertical drift from ground-based JULIA coherent radar, and IVM's meridional drift (vertical component at the equator) is presented in this study. Three main results are discussed in this …