This study investigates the impact of varying soot aerosol concentrations and relative humidity (RH) on the polarizability and phase function of non-spherical urban atmospheric aerosols. Using the Optical Properties of Aerosols and Clouds (OPAC 4.0) software, urban aerosol optical properties at visible wavelengths (0.4 - 0.8 μm) were simulated across eight relative humidities (0%, 50%, 70%, 80%, 90%, 95%, 98%, 99%). The Stokes parameters are employed to derive phase functions, while the Claussi-Massoti formulation, combined with Maxwell and Lorentz-Lorentz relations, were used for computation of effective polarizabilities. The results provide insights into RH and soot aerosol concentration effects on urban aerosol optical properties, including effective polarizabilities, polarization, and phase function data. The extraction of these data using OPAC 4.0 and determination of aerosol size growth curves' mean exponent through effective hygroscopic growth. Effective polarizability exhibits a decrease with increasing wavelength and soot aerosols concentration, whereas it increases with increasing relative humidity.