  A critical assessment of the available calculations of the top quark width is
presented. QCD corrections, the finite mass of the $b$ quark and the effect of
the $W$ width are included as well as the electroweak corrections. The relative
importance of these corrections is demonstrated for the realistic range of top
masses. For the QCD corrected decay rate we use the formulae from \cite{JK1}
and include the electroweak correction taken from \cite{DS}. Our results differ
from those available in the literature because all the later calculations
ignored the effect of W width discussed earlier in \cite{JK1}~. This leads to
an effect comparable in size to the electroweak correction.
