Physical activity-related workplace interventions can be counterstrategies for physical inactivity due to office work. Newly introduced programs should be evaluated for success. This study aimed to evaluate the intervention of a workplace active rest program and to compare a prospective and retrospective design of evaluation. A Germany-wide multicenter evaluation of a 3-month workplace active rest program (30 min, once a week) was carried out at 14 locations with a longitudinal pre/post design by means of an anonymous questionnaire (npre = 405, npost = 369). The participants’ program-related changes in targeted characteristics regarding posture, function, complaints and physical awareness were collected with a questionnaire in a prospective design and afterward retrospectively. The prospective evaluation showed a significant improvement in the target characteristic “postural muscles in the neck area”. In the retrospective survey, all target characteristics improved significantly. There were no differences between locations. The workplace active rest program in this study had positive effects on the perception of postural neck muscle status regardless of prospective or retrospective approach. Selection of survey mode should depend on desired outcome and consecutive influencing factors. In this specific case, retrospective survey could give more indirect information about overall satisfaction with the program and job although being influenced by response bias. Recall bias should be relatively small for shorter time periods assessed. Future studies should account for corresponding bias and specifics of target characteristics regardless of the chosen approach to survey.