BACKGROUND Spending time outdoors can reduce stress, and integrating short, regular outdoor office work into daily routines may be an innovative approach to alleviating workplace stress, which is a growing global concern. OBJECTIVE To evaluate the feasibility of an outdoor office work intervention with stress monitoring among office workers, to examine its associations with perceived and physiological stress and document facilitators and barriers using digital tools. METHODS In a 2–week pilot study (2022) of office workers in Sweden, participants worked indoors during week 1 (baseline) and outdoors for ≥30 min per day during week 2 (intervention). During work hours, an online digital questionnaire collected daily perceived stress ratings (1–10 scale), while heart rate variability (HRV) was recorded using the Firstbeat Bodyguard 3. Facilitators and barriers to outdoor office work were documented through photographs using the Stanford Our Voice Discovery Tool app. Stress data were analysed with linear mixed model (random intercept for participant). Photographs were coded using a reflexive thematic analysis. RESULTS The protocol was found to be feasible with high data completeness (93%-88%) and adherence to the study protocol (89%). Seven participants provided 10 days of repeated stress measures over the 2-week study period. Mean perceived stress decreased from then baseline week through the end of the outdoor office intervention week, with mean change of −1.0 (95% CI −1.7 to −0.3; P=.01). For HRV, frequency–domain measures decreased during the intervention compared with baseline: very low frequency (VLF) −19.7 ms² (95% CI −38.2 to −1.2; P=.037) and the low frequency (LF) decreased compared with baseline: −98.8 ms² (95% CI −187.6 to −10.0; P=.03). Photo analysis of 70 images yielded five themes—State of Being, Nature Environment, Comfort or Convenience, Current Norms, and Urban Settings—each containing specific elements acting as facilitators or barriers to outdoor office work. CONCLUSIONS Overall, this small pilot study’s design using digital tools, and high data completeness and adherence support the feasibility of this intervention in real–world office settings, though some adjustments are required. The reduction in perceived stress in the week where participants were working outdoors suggests that outdoor office work may be a promising strategy for addressing work–related stress and worthy of further exploration. However, HRV indices indicate decreased autonomic system variability and possibly increased physiological stress. Though likely multi-faceted, contextual factors identified through analysis of photographs may help explain this discrepancy.