In this study, fatigue performance and fracture behavior of interstitial-free, low carbon and phosphorus-added low carbon steels have been investigated by plane bending fatigue tests at room temperature in air. For all steels, fatigue tests were carried out at a frequency of 1000 cycles per minute, however, a limited number of specimens of low carbon steel were also tested at frequencies of 500 and 1500 cycles per minute. After all mechanical tests, fracture surfaces were cut and examined using scanning electron microscopy to identify the fracture features. At any applied stress level, low carbon steel showed better fatigue performance than interstitial-free steel, and phosphorus addition further improved the fatigue life of low carbon steel. Fractographic observations on fatigue fracture surfaces revealed transgranular fracture for low carbon steel and intergranular fracture for interstitial-free steel. Interestingly, addition of 0.12 wt.% of phosphorus in low carbon steel could not change the dominant transgranular fracture behavior of the steel.