The shutdown of Spirit Airlines over the weekend has created a capacity gap of approximately 5% in the US ultra-low-cost carrier market. Executives at Frontier Airlines stated on Tuesday that, due to its highly overlapping route network with Spirit, the company is well-positioned to absorb a significant portion of the demand left behind by its former competitor.

Frontier CEO James Dempsey noted during an earnings call that the airline has direct route overlap with the defunct Spirit on more than 100 routes, an advantage unmatched by other carriers. The company estimates that Spirit's exit alone will contribute approximately 2 percentage points to unit revenue growth in the second quarter. Chief Commercial Officer Robert Schroeter added that, based on previous experience with Spirit's capacity adjustments, the company believes this market exit could lead to a 3% to 5% increase in unit revenue.

Frontier is actively increasing capacity in markets previously dominated by Spirit, including Dallas-Fort Worth, Detroit, Fort Lauderdale, Las Vegas, and Orlando.

However, the company is simultaneously facing pressure from soaring fuel costs. Influenced by the Iran conflict, jet fuel prices surged to $4.51 per gallon at the end of April, significantly higher than the $2.24 per gallon assumed in Spirit's bankruptcy reorganization plan. Frontier anticipates its second-quarter fuel cost will be approximately $4.25 per gallon and forecasts a quarterly loss between $0.45 and $0.60 per share, exceeding analyst expectations of a $0.43 per share loss.

Despite this, several Wall Street investment banks believe Spirit's closure eliminates Frontier's strongest price competitor on dozens of overlapping routes, which is expected to drive up airfare prices and solidify market share. Analysts at Jefferies stated, "All else being equal, Spirit's cessation of operations reduces competitive capacity in the market and removes the lowest fare option typically available to consumers. As market share consolidates upward, prices are likely to increase."