Low-cost airlines are convenient and often cheaper than their full-service counterparts. Costs are lower because fewer services are offered and consumers have lower expectations of their services. In this case study, students will be asked to analyze consumer expectations of the sustainability initiatives implemented by low-cost carriers; more precisely, do consumers have similar lower expectations regarding the sustainability initiatives that low-cost carriers implement? This case study focuses on one low-cost airline, Allegiant Air, and analyzes its sustainability initiatives as linked to the sustainable development goals (SDGs) outlined by the United Nations and specifically applied to the aviation industry. The findings conclude that Allegiant Air is doing well in regard to the financial and social SDGs but is lacking in the environmental actions. The 2020 COVID-19 pandemic and the reopening of this industry may be the opportunity to address sustainability issues and put new practices into place.