An experimentally validated model is proposed for the effect of fastener mean stress on its high cycle fatigue (HCF) performance. The model is also used for comparing fatigue performance of ultra-high strength (UHS) fasteners Class 14.8, 15.8 and 16.8 with that of commercially available (CA) Class 10.9 and 12.9 fasteners. Respective mean stress-adjusted S-N curves are constructed using experimental data following applicable ASTM standards. Proposed model results are compared with other existing models that account for the effect of mean stress such as Goodman, Gerber, Morrow, Soderberg, and Elliptic (ASME) models. Detailed discussion of the results, failure mode, and conclusions are provided.