In this study the environmental costs and benefits of smart metering technology systems installed in households in Norway have been assessed. Smart metering technology systems enable mechanisms to manage electricity consumption by shifting loads. With the use of Life Cycle Assessment (LCA) and the ReCiPe method for impact assessment, the life cycle impacts of installation and operation of a system in a household have been found. Environmental benefits of using the systems to manage electricity consumption have been quantified. The results of the study indicated that the environmental costs of smart metering technology systems mainly are caused by the production of system components and system electricity use during operation. For the production of system components, the use of electronics in the components was generally the major contributor to the total environmental impacts. Further, the systems metal depletion potential was high relative to other environmental impacts after normalization in impact assessment. The main environmental benefits of smart metering technology systems in a Norwegian perspective will be in a critical supply situation of electricity to avoid use of reserve capacity gas power plants, and the results from the study showed that the systems in such a case can contribute to an avoided emission of greenhouse gases. Load shifting from a general basis may however not always have environmental benefits and this will depend on the existing alternatives for electricity production.