Energy efficient retrofit of historic urban stock requires a methodical approach, comprehensive analysis and case-specific solutions. In large scale rehabilitation projects, the retrofit strategy should be developed on how to decide solutions for buildings providing the most energy saving in a short time. This paper presents a pilot study conducted at the neighborhood scale, consisting of 22 pre- and early-republican residential and contemporary buildings in a historic urban fabric of İzmir, Turkey. It aims to develop an integrated approach to identify case-specific energy efficient solutions for retrofit strategy of larger scale historic district. It utilizes building performance simulation (BPS) model, created through the documentation and quick field survey. All case buildings are grouped under three main categories considering their heritage value and building characteristics. Two retrofit packages and three individual operational solutions are constituted by considering five-leveled retrofit impact assessment of the CEN EN 16883:2017 Standard. Within the integrated approach, energy classes of the buildings are calculated regarding Building Energy Regulation of Turkey. Most-related two design parameters, S/V and ground floor area to conditioned volume ratio, on annual energy consumption of the buildings in current cases are identified by Pearson correlation analysis. The simulation results indicated that, three buildings including Building 8, 11 and 21 representing each group can initially be retrofitted. Building 11 has the most energy saving potential through Package 2 in its own group. For all buildings, while maximum energy saving was provided by Package 2 with 48,57%, minimum energy saving obtained from Package 1 with 19,8%.