An approach is provided to determine answer stability in a question answering (QA) system. In the approach, a question submitted to a question answering (QA) system is selected and data pertaining to a candidate answers generated by the QA system are analyzed. The analysis of the data results in a stability characteristic that pertains to the candidate answers. A confidence value associated with the candidate answers is adjusted based on the respective answer's stability characteristic. One or more of the candidate answers are provided to a requestor based on the adjusted confidence values.