For high‐current circular machines like the SIS100, which has been proposed as driver for a future radioactive beam facility at GSI, an exploratory study of space charge effects on resonances during long‐term beam storage is indispensable. We discuss the effect of space charge on sextupole error resonances by a 4D model using an analytical expression for a stationary space charge. The effect of space charge induced resonance crossing in a bunch beam is approached by a simplified model.