Well performance evaluation and prediction via decline curve analysis (DCA) requires defined abandonment conditions (Abandonment BSW and oil rate) to estimate the developed ultimate recovery (DUR) of a drainage point. Abandonment BSW and oil rate are derived from well models which require abandonment reservoir pressure and Gas-oil-ratio (GOR) among others as inputs. Good understanding of the performance of a reservoir is necessary for the prediction of abandonment GOR, and this prediction requires a systematic approach. The assumed value of producing GOR has a direct impact on the magnitude of the hydrostatic and dynamic pressure loss in a production tubular and hence it is a very important parameter in the vertical lift performance of a well. Similarly, the the reservoir pressure at abandonment is an indication of the energy available from the reservoir for lift hydrocarbon fluid s from the bottom of the producing wells. This paper illustrates the methodology employed for the estimation of abandonment reservoir pressure, GOR and BSW in support of well performance evaluation and reservoir management. Case studies for saturated and undersaturated reservoirs with weak-to moderate aquifers are considered.