This explanatory sequential mixed-method study explored the factors associated with the investment (or not) in sit-stand workstations (SSWs) and alternative initiatives to reduce prolonged sitting at work from the perspective of furniture purchasing decision-makers in Australian workplaces. Participants (n = 270) from >200 organisations across 19 industry sectors completed an online survey. Seven interviews were conducted in a sub-sample of participants from organisations without SSWs. The majority (80%) of workplaces reported having invested in SSWs. Workplaces without SSWs, opposed to those with SSWs, were more likely to be private (79.6% vs. 43.5%), of small/medium size (70.4% vs. 35.6%) and without a wellness program (57.4% vs. 22.2%) (all p < 0.05). Financial implications were the main reason for not investing in SSWs. Exercise and stretch breaks were alternative initiatives to reducing sedentary behaviour at work. Better evidence on the return on investment is needed to support purchasing decisions on SSWs.