This study investigates the impact of the parameterization of dry deposition on the local gas-particle partitioning between ammonium nitrate NH4NO3 and its precursor gases (ammonia, NH3 and nitric acid, HNO3) through chemistry-coupled large-eddy simulations on the dispersion of reactive gaseous and particulate pollutant in an idealized street canyon. A key factor in the parameterization of dry deposition is the effective Henry's Law constant H*. Three distinct characterizations of H* are compared: two drawn from existing literature (referred to as Model 1 and Model 2) and one typical of low pH conditions (referred to as Model 3), which could be more representative of urban areas. Model 3 shows contrasting gas-particle partitioning results between NH3, HNO3, and NH4NO3 with Model 1 and Model 2. In detail, the NH4NO3 concentrations in the street of Model 1 and Model 2 are smaller than the background NH4NO3 concentration. However, Model 3 shows higher NH4NO3 concentration in the street than the background NH4NO3 concentration. This is because the dry deposition fluxes of NH3 and HNO3 are higher in Model 1 and Model 2 than in Model 3, resulting in less available NH3 and HNO3 for NH4NO3 formation. These findings highlight the importance of selecting an appropriate H* characterization that is tailored to the specific environmental conditions under investigation.