The purpose of energy benchmarking is to promote efficient use of energy. Knowing that the energy used by a building is excessive is the first step in making positive changes. Based on an energy benchmark, one can estimate the potential in energy and cost savings when pursuing better performance.This thesis developed weather normalized energy benchmarking of 45 gas-heated high-rise multi-unit residential buildings (MURBs) in Toronto. The weather normalized annual energy consumption (NAC) was calculated by the PRInceton Scorekeeping Method (PRISM). The NACs are in the range from 242 to 453 kWh/m2. The energy saving assessment showed that 24 MURBs had NACs changes, which ranged from 45.6 kWh/m2 increase to 103.7 kWh/m2 decrease.The NACs, calculated by the simple ratio weather normalization (SRWN) method and ENERGY STAR® Portfolio Management (PM) method were comparable to PRISM results. However, the SRWN method tends to overestimate the energy saving by 23% while PM underestimates it by 21%.