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• Fatigue resistance of press hardened steels may be assessed by fracture mechanics. • Fatigue of press hardened 22MnB5 steels is controlled by pre-existent surface defects. • Defect size distribution and location is essential to obtain good fatigue estimations. • Crack resistance properties can be used to estimate the fatigue limit. In press hardened steels, fatigue behaviour is very sensitive to surface defects or irregularities, either intrinsic or introduced during trimming operations. This work addresses the understanding and prediction of fatigue resistance of press hardened steels from a fracture mechanics approach. The size of fatigue originating defects were evaluated and used to estimate the fatigue limit for different surface conditions (coated and uncoated), different coatings (Al-Si and Zn) and different edge condition (polished and mechanically trimmed). Good agreement was found between calculated and experimental values, which shows the potential of fracture mechanics to estimate the fatigue performance of press hardened steels. [ABSTRACT FROM AUTHOR]