A within-person diary research design with 39 full-time workers was used to examine the effects of daily cross-domain usage of information and communication technologies (ICTs) on job-related performance and stress in both workplace and home domains. Segmentation preference effects on links between cross-domain ICT usage and both job performance and job stress were also analyzed. A positive association was found for the first relationship in mixed home-workplace contexts, and a negative association for the second in home contexts only. A stronger segmentation preference effect on the negative relationship between cross-domain ICT usage and job stress was found for integrators (employees who integrate work and home domains) compared to separators (employees who separate work/non-work activities). Our findings suggest that daily cross-domain ICT usage can enhance job performance and reduce job stress, with a moderating effect of segmentation preference on the link between cross-domain ICT usage and job stress.