Existing parameterizations tend to underpredict the ?-pinene aerosol mass fraction (AMF) or yield by a factor of 2?5 at low organic aerosol concentrations (<5 µg m^?3). A wide range of smog chamber results obtained at various conditions (low/high NO_x, presence/absence of UV radiation, dry/humid conditions, and temperatures ranging from 15?40°C) collected by various research teams during the last decade are used to derive new parameterizations of the SOA formation from ?-pinene ozonolysis. Parameterizations are developed by fitting experimental data to a basis set of saturation concentrations (from 10^?2 to 10⁴ µg m^?3) using an absorptive equilibrium partitioning model. Separate parameterizations for ?-pinene SOA mass fractions are developed for: 1) Low NO_x, dark, and dry conditions, 2) Low NO_x, UV, and dry conditions, 3) Low NO_x, dark, and high RH conditions, 4) High NO_x, dark, and dry conditions, 5) High NO_x, UV, and dry conditions. According to the proposed parameterizations the ?-pinene SOA mass fractions in an atmosphere with 5 µg m^?3 of organic aerosol range from 0.032 to 0.1 for reacted ?-pinene concentrations in the 1 ppt to 5 ppb range.