Cost-utility analysis is used to inform the allocation of healthcare resources, using the quality-adjusted life year (QALY) as the outcome measure. We report the development of an epilepsy-specific QALY measure (NEWQOL-6D) derived from the NEWQOL measure of health-related quality of life. Firstly, psychometric and Rasch analyses established the dimension structure of NEWQOL and generated a reduced health state classification system including one item per dimension. Secondly, health states generated by the classification system were valued using Time Trade Off, and the results were modeled to generate a utility score for every health state. A classification system with 6 dimensions (worry about attacks; depression; memory; concentration; stigma; control) was produced, and generalized least squares regression was used to generate utility scores for every health state. This study is the first attempt to derive an epilepsy-specific QALY measure, and the utility values can be used in the economic evaluation of emerging technologies for epilepsy.