Existing academic literature is inconclusive about characteristics and viability of the long-haul low cost airline business model, whereas several airlines of this type are emerging. This article aims to validate its defining characteristics by clustering a sample of 37 transatlantic airlines using principal component and hierarchical cluster analyses along a newly constructed long-haul airline business model framework. To contribute to the evaluation of business model viability, cost differences between clusters are uncovered subsequently followed by a discussion of their sustainability. Key findings include the characterization of the emerging long-haul LCC business model and its significant differences from existing legacy hub and leisure carrier models. On a cluster average, 33% lower unit costs compared to legacy hub carriers were identified, of which 24 percentage points were evaluated as sustainable.