The real space transfer in depletion‐mode dipole heterostructure field‐effect transistors (HFETs) has been investigated both theoretically and experimentally. Theoretically, we demonstrate that parallel conduction will be substantially reduced in the dipole HFET and to a smaller extent in the planar‐doped HFET when compared to the conventional HFET due to the increased carrier confinement. By measuring the cutoff frequency at various dc biases, the experimental results indicate that a reduced real space transfer effect occurs in the depletion‐mode dipole HFETs.