The influence of load ratio on the high cycle fatigue (HCF) and very high cycle fatigue (VHCF) properties of shot-peened VDSiCr spring steel is investigated. S-N curves are measured with ultrasonic fatigue testing equipment at load ratio R = -1, R = 0.1 and R = 0.5 up to 10(10) cycles. Failures either occur below 5 x 10(6) or above 5 x 10(8) cycles. In the HCF regime cracks start exclusively at the surface. In the VHCF regime crack initiation occurs solely in the interior, at grain boundaries, inclusions or (rarely) in the matrix. The S-N curves continue to decrease beyond 10(9) cycles, most pronounced for R = -1 where the mean cyclic strength at 10(10) cycles is 5 % lower than at 10(9) cycles. VHCF strength presented in a Haigh diagram can be very well approximated with a straight line. The mean stress sensitivity factor is M = 0.47 for load ratios between R = -1 and R = 0.5.