In a semiconductor the density of carriers in each subband fluctuates owing to intraband transitions. We consider the spectral density for number fluctuations and for conductance fluctuations arising from such intraband transitions. It is shown that the spectral density for number fluctuations equals zero. If the mobility is the same in all subbands, the spectral density for conductance fluctuations equals zero. Otherwise the conductance fluctuations show a non‐1/ fspectrum.