As sewerage systems have obsolete, as quality and service level standards increase, and as rain characteristics change, the sewerage utility authorities are challenged to develop cost recovery strategies that assure financial sustainability. In this study, we conducted scenario analysis to examine the effect of three alternatives of partial or full sewerage cost recovery in Seoul during 2014-30 periods. It turned out that the alternative 1 is optimal and recommended. According to alternative 1, we had better increase annually sewerage fee by 14.8% until 2020 and thereafter apply only the inflation rate in setting sewerage fee. It would gradually decrease the deficit after 2019. The accumulated deficit of 13 billion Won in 2030 was estimated. We expect that this kind of analysis may provide useful informations to help sewage utility staffs, decision makers, and regulatory authorities understand, develop and implement ultimate full cost recovery strategy for many municipalities.