Southwest Airlines Co.

Southwest Airlines Co. is the largest domestic airline in the United States by passengers carried, operating an all-Boeing 737 fleet of approximately 800 aircraft and generating $28.1 billion in operating revenue in fiscal 2025. The Dallas-based carrier serves over 120 destinations across the United States and near-international markets, holding the number-one market position at nearly half of the 50 largest U.S. airports.

This is a story about an iconic American franchise attempting the most ambitious business-model transformation in airline history — and the early evidence that it is working. Over eighteen months spanning 2025 and early 2026, Southwest introduced assigned seating, extra-legroom products, baggage fees, a basic-economy fare, flight-credit expiration, redeye flying, six new airline partnerships, and a reworked co-brand credit-card agreement with Chase — while simultaneously cutting $370 million in cost from the enterprise and executing the first corporate layoff in company history. That any one of these changes would be significant for an airline of Southwest's size and cultural weight is notable; that they were all delivered on time, without operational disruption, and while the airline earned the Wall Street Journal's ranking as the Best U.S. Airline of 2025, is extraordinary.

The central question has shifted from "can Southwest change?" to "how much does the change earn?" In January 2026, management guided full-year adjusted EPS of at least $4 — dramatically above the $0.93 posted for 2025. By the Q1 2026 call in April, a surge in fuel prices tied to geopolitical disruption had introduced a $0.22 per-share headwind in the first quarter alone and a roughly $1 billion second-quarter headwind, or 10 points of margin. The company did not pull guidance but declined to update it, citing fuel volatility that makes the outcome genuinely uncertain. The core transformation is on track; the question is whether the revenue engine can outrun the fuel bill. The answer will reveal whether the new Southwest is a structurally higher-margin business or a familiar low-cost carrier operating in a temporarily favorable pricing environment.