To make robust judgments of an energy efficiency programme's economic effectiveness, we need to know how much energy and CO2 is actually being saved through the financial support it provides. But most evaluations of home retrofit energy efficiency programmes depend on calculated, rather than measured, levels of energy consumption. This fails to take into account the discrepancies that have been observed in practice, between calculated and actual energy consumption both before and after refurbishment. Evaluations of energy efficiency programmes ideally need to consider rebound effects, free rider effects, reduced savings due to insufficient technical quality, and discrepancies between actual and calculated pre-refurbishment energy consumption. This paper investigates and compares evaluations of two prominent energy efficiency programmes in the Germany and UK-the CO2-Building Rehabilitation Programme and the Supplier Obligation. We show that evaluations of the Supplier Obligation explicitly address most of the reduction effects whereas this is not the case for the CO2-Building Rehabilitation Programme. (C) 2013 Elsevier B.V. All rights reserved.