Theoretical parameterizations for the size-resolved scavenging coefficient for atmospheric aerosol particles scavenged by snow (Λ<sub>snow</sub>) need assumptions regarding (i) snow particle–aerosol particle collection efficiency <i>E</i>, (ii) snow-particle size distribution <i>N(D</i><sub>p</sub>), (iii) snow-particle terminal velocity <i>V</i><sub><i>D</i></sub>, and (iv) snow-particle cross-sectional area <i>A</i>. Existing formulas for these parameters are reviewed in the present study, and uncertainties in Λ<sub>snow</sub> caused by various combinations of these parameters are assessed. Different formulations of <i>E</i> can cause uncertainties in Λ<sub>snow</sub> of more than one order of magnitude for all aerosol sizes for typical snowfall intensities. <i>E</i> is the largest source of uncertainty among all the input parameters, similar to rain scavenging of atmospheric aerosols (Λ<sub>rain</sub>) as was found in a previous study by Wang et al. (2010). However, other parameters can also cause significant uncertainties in Λ<sub>snow</sub>, and the uncertainties from these parameters are much larger than for Λ<sub>rain</sub>. Specifically, different <i>N(D</i><sub>p</sub>) formulations can cause one-order-of-magnitude uncertainties in Λ<sub>snow</sub> for all aerosol sizes, as is also the case for a combination of uncertainties from both <i>V</i><sub><i>D</i></sub> and <i>A</i>. Assumptions about dominant snow-particle shape (and thus different <i>V</i><sub><i>D</i></sub> and <i>A</i>) will cause an uncertainty of up to one order of magnitude in the calculated scavenging coefficient. In comparison, uncertainties in Λ<sub>rain</sub> from <i>N(D</i><sub>p</sub>) are smaller than a factor of 5, and those from <i>V</i><sub><i>D</i></sub> are smaller than a factor of 2. As expected, Λ<sub>snow</sub> estimated from empirical formulas generated from field measurements falls in the upper range of, or is higher than, the theoretically estimated values, which can be explained by additional processes/mechanisms that influence field-derived Λ<sub>snow</sub> but that are not considered in the theoretical Λ<sub>snow</sub> formulas. Predicted aerosol concentrations obtained by using upper range vs. lower range of Λ<sub>snow</sub> values (a difference of around two orders of magnitude in Λ<sub>snow</sub>) can differ by a factor of 2 for just a one-centimetre snowfall (liquid water equivalent of approximately 1 mm). Based on the median and upper range of theoretically generated Λ<sub>snow</sub> and Λ<sub>snow</sub> values, it is likely that, for typical rain and snow events, the removal of atmospheric aerosol particles by snow is more effective than removal by rain for equivalent precipitation amounts, although a firm conclusion requires much more evidence.