The wave functions for calculating gas phase 19 F chemical shifts were optimally selected using the factorial design as a multivariate technique. The effects of electron correlation, triple-ξ valance shell, diffuse function, and polarization function on calculated 19 F chemical shifts were discussed. It is shown that of the four factors, electron correlation and the polarization functions affect the results significantly. B3LYP/6-31+G(df,p) wave functions have been proposed as the best and the most efficient level of theory for calculating 19 F chemical shifts. An additional series of fluoro compounds were used as a test set and their predicted 19 F chemical shifts values confirmed the validity of the approaches.