In this paper we propose a method to gain access to the top -quark width which exploits off-shell regions in the process e+e -> W+ W- bb(-). Working at next-to leading order in QCD we show that carefully selected ratios of off-shell regions to on-shell regions in the reconstructed top and anti-top invariant mass spectra are, independently of the coupling gtbw, sensitive to the top -quark width. We explore this approach for different centre of mass energies and initial-state beam polarisations at e(+)e(-) colliders and briefly comment on the applicability of this method for a measurement of the top -quark width at the LHC.