We investigate the consequences of delay in the iodate–arsenous acid reaction under the influence of an electric field at a constant current density. Using the charge balance condition, we show how the electric field may induce an intrinsic delay in the system, which gives rise to instability. The different instability regions in the appropriate parameter space are examined. We show how the delay incites an absolute instability in a system otherwise displaying varied wave-front characteristics, viz., convective and absolute instabilities and also stationary patterns