We examine halo gas cross sections and covering fractions, f c, of intermediate-redshift Mg ii absorption selected galaxies. We computed statistical absorber halo radii, R x, using current values of dN/dz and Schechter luminosity function parameters, and have compared these values to the distribution of impact parameters and luminosities from a sample of 37 galaxies. For equivalent widths W r (2796)⩾ 0.3 �, we find 43⩽ R x⩽ 88 kpc, depending on the lower luminosity cutoff and the slope, β, of the Holmberg-like luminosity scaling, R∝ L β. The observed distribution of impact parameters, D, are such that several absorbing galaxies lie at D> R x and several non-absorbing galaxies lie at D< R x. We deduced that f c must be less than unity and obtain a mean of< f c>∼ 0.5 for our sample. Moreover, the data suggest that halo radii of Mg ii absorbing galaxies do not follow a luminosity scaling with β in the range of 0.2–0.28, if f c= 1 as previously reported. However, provided f c∼ 0.5, we find that halo radii can remain consistent with a Holmberg-like luminosity relation with β≃ 0.2 and