Electron capture times in a quantum well (QW) structure with finite electron density are calculated for electron‐electron (e‐e) and electron‐polar optic phonon (e‐pop) scattering. We find that the capture time oscillates as function of the QW width for both processes with the same period, but with very different amplitudes. For an electron density of 1011 cm−2 the e‐e capture time is 101−103 times larger than the e‐pop capture time except for QW widths near the resonance minima, where it is only 2−3 times larger. With increasing density the e‐e capture time decreases and near the resonance becomes smaller than the e‐pop capture time. Our e‐e capture times are three orders larger than the results of Blom etal. [Appl. Phys. Lett. 62, 1490 (1993)]. The role of the e‐e capture in QW lasers is therefore readdressed.