Orientation: Recently, a new work-nonwork interference instrument was developed to measure the interference between work and nonwork roles in the South African context (Koekemoer, Mostert & Rothmann, 2010). However, no information is available on the psychometric properties of this instrument.Research purpose: The objectives of this study were to investigate the internal validity (construct, discriminant and convergent validity), reliability and external validity (relationship with theoretically relevant variables, including job characteristics, home characteristics, burnout, ill health and life satisfaction) of the instrument.Motivation for the study: Work-family interaction is a key topic receiving significant research attention. In order to facilitate comparison across work-family studies, the use of psychometrically sound instruments is of great importance.Research design, approach and method: A cross-sectional survey design was used for the target population of married employees with children working at a tertiary institution in the North West province (n = 366). In addition to the new instrument, job characteristics, home characteristics, burnout, ill health and life satisfaction were measured.Main findings: The results provided evidence for construct, discriminant and convergent validity, reliability and significant relations with external variables.Practical/managerial implications: The new instrument can be used by researchers and managers as a test under development to investigate the interference between work and different nonwork roles (i.e. parental role, spousal role, work role, domestic role) and specific relations with antecedents (e.g. job/home characteristics) and well-being (e.g. burnout, ill health and life satisfaction).Contribution/value-add: This study provides preliminary information on the psychometric properties of a new instrument that measures the interference between work and nonwork.