Messages to reduce sedentary behaviour often encourage walking and standing breaks from sitting (BFS; e.g., standing during meetings). However, we know very little about how willing adults are to take these breaks and what influences their decisions to take BFS. Knowing this would allow researchers and practitioners to construct more effective interventions and messaging campaigns. This study explores working adults' likelihood of taking various break types and the factors affecting their decisions to (not) engage in each break. Participants (n=291) rated their likelihood of engaging in 13 home- and work-based BFS (e.g., standing/walking during commercials, while on the phone, while doing chores) using seven-point scales (very unlikely-very likely), and elaborated on the reason(s) for each rating. Standing/walking while doing chores was the most favoured break, while standing during meetings was the least favoured. Factors across several socio-ecological dimensions emerged as facilitators and inhibitors of BFS, including influences at the individual level (current habits and preferences, attitudes towards BFS, and the personal benefits and drawbacks of BFS), at the social and organizational levels (peer attitudes and behaviour, workplace norms and expectations, and the social benefits and drawbacks of BFS), and at the environmental level (physical and technological environments). Finally, each type of break had its own unique group of influences, suggesting that BFS should likely not be considered as one behaviour, but instead, be treated as distinct.