Interest and effort in re-introducing civil supersonic transport (SST) airplanes as a means of travel have surged in the past decade. Current major endeavours are underway for both commercial and business supersonic vehicles. The value proposition for these aircraft exists for high-net-worth individuals and business-class travellers who value time savings more than the potential cost associated with supersonic travel. One important driver for the higher travel cost is the increase in fuel consumption for an SST due to higher cruise speeds. Even though the new SSTs in development should be more fuel-efficient than SSTs of the past, comparing to a subsonic aircraft flying the same routes, an SST that burns more fuel while having fewer passengers (pax) on board per trip yields significantly higher fuel burn per passenger for these operations. However, due to the higher ticket costs and other limitations such as noise and emissions, supersonic commercial operation is not expected to capture a large portion of the aviation market. This means that in the broader scope of global aviation, the effect of increased fuel burn per pax on fleet-level carbon dioxide (CO2) emissions is unknown. Also, due to uncertainties in the effectiveness of sonic boom reduction technologies, it remains unclear whether supersonic over-land flight will be permitted in the future. This study formulates a methodology that employs a bottom-up approach for estimating the demand for supersonic commercial operations in the coming decades, using only publicly available subsonic baseline-fleet data. The scope of this work focuses specifically on the supersonic commercial aviation market and does not consider the supersonic business jet market. The constraints and limitations identified while using publicly available data is key to understanding the data requirements for executing market assessment studies of this type. The bottom-up methodology for demand estimation is implemented, and the environmental impact of the estimated market is determined. The results identify a supersonic commercial flight demand of 34–776 daily, global flights in 2035, growing to 52–1164 in 2050, corresponding to low and high demand scenarios, respectively. These fleets will contribute approximately 1.43–28.25 megatonnes (MT) of CO2 to global aviation emissions in 2035, growing to 2.20–42.50 MT of CO2 in 2050. These emissions in 2035 and 2050 represent a 0.16–3.08% and 0.24–4.63% increase in CO2 emissions with respect to the 2018 global subsonic commercial aviation fleet.