  We present new results on the lifetimes and widths of $B$ hadrons based on
300-450 pb$^{-1}$ of data collected by CDF and D{\O}at the Fermilab Tevatron.
Lifetimes were measured in semileptonic decays as well as fully reconstructed
hadronic modes. A new measurement of the width difference between $B_s$ CP
eigenstates, $\Delta\Gamma / \bar{\Gamma} $, in $B_s$ decays to $J/\psi \phi$
is also presented.
