The mechanism of oxygen transport in the bulk silicon melt with and without crystal pulling were investigated experimentally and computationally. Crucible rotation rates were chosen as a parameter, and results suggest that rotation suppresses transport of oxygen from the crucible wall to the crystal growth interface, while calculations indicated the crucible bottom as the oxygen source when the crystal is pulled. The temperature distribution across the crucible bottom, possibly the impetus of the flow, was the most important term in control of the oxygen concentration in silicon single‐crystal growth.