Business model development at low-cost and full-service airlines throughout the years has led to a departure from the original models. The low-cost model is shifting up-market to capture higher yield traffic, while the full-service model is adopting low-cost model elements to achieve optimization. This paper determines how the degree of adherence to either original model impacts the profit level of low-cost carriers and full-service carriers. The methodology studies 26 North American and European airlines, 12 low-cost and 14 full-service, and evaluates each polarized group’s 2004 product and operational features against the original models. Evaluation occurs on an ordinal scale and is derived from secondary data sources to present the level of transition from the original model. Analyses results show that profit levels are directly correlated to adherence to the original model, at both extremes, while those carriers diverging most from the traditional models experience lower profit levels.