The simple phenomenological model developed by Maffettone and Minale (J Non-Newt Fluid Mech 78:227-241, 1998) for the deformation of a single ellipsoidal drop in a viscous flow is extended here to predict the drop deformation in confined viscous flows. The model is capable of describing the transient evolution of an ellipsoidal drop subjected to a generic flow field. The steady-state predictions are analytical and recover the theoretical limits of Shapira and Haber (Int J Multiph Flow 16:305-321, 1990) for steady small deformation of a drop in a confined simple shear flow. Model predictions are compared with data available in the literature that cover a wide range of parameter values, and the agreement is good.