The Western 24 h society poses great psychological and physical demands on people, which may result in complaints such as stress or being overworked, and reduced immune fitness. Having a holiday may be a good way to reduce work-related stress and reduced mood and improve perceived immune fitness. Therefore, the aim of the current study was to assess the impact of having a holiday or work on perceived immune fitness and mood. A survey was held among N = 246 young adults who were on holiday in Fiji, and N = 87 subjects who were in Fiji for work. The sample comprised both students and individuals with a job at home. Past year immune status was assessed with the Immune Status Questionnaire (ISQ). Current perceived immune functioning and mood were rated from 0 (very poor) to 10 (excellent). Assessments were made for two occasions: (1) the current situation (in Fiji), and (2) at home (before traveling). Compared to being at home, both students and working individuals on holiday in Fiji reported significantly improved immune fitness and significantly improved mood. For example, both groups reported reduction of stress of about 60% while in Fiji. In students who came to Fiji for work or spending a holiday, improvements in perceived immune fitness were more pronounced than in working people coming on holiday in Fiji. In contrast, working people on holiday reported greater improvements in mood compared to students. The magnitude of improvements were significantly greater among women than men. In conclusion, the data suggest that both having a holiday or working in Fiji is associated with significant improvements of mood, which were themselves associated with improved immune fitness. The findings are of importance for the tourism industry as they demonstrate that, in addition to leisure (or being active) as a purpose for having a holiday, the observed mental health benefits and improved perceived immune fitness provide an additional motive to have a holiday.