Shares of Southwest Airlines (LUV) plummeted 5.56% in pre-market trading on Thursday, reacting to the company's cautious forward outlook despite reporting second-quarter results that significantly surpassed Wall Street profit expectations.

The sell-off was triggered by Southwest's revised full-year 2026 adjusted earnings per share guidance, now forecast at $3.25 to $4.25, a notable reduction from its prior outlook of "at least $4.00." The company also issued a third-quarter adjusted earnings forecast of $0.50 to $0.75 per share, falling well short of the analyst consensus of $0.82. While the airline achieved record revenue and saw its adjusted earnings per share of $0.94 crush estimates, driven by a business model overhaul that introduced assigned seating and baggage fees, these gains were overshadowed by a staggering 67% surge in fuel expenses, which reached $2.22 billion for the quarter.

The broader airline industry is grappling with severe jet fuel price volatility stemming from escalating U.S.-Iran tensions, and Southwest's lower outlook signals that the impact of geopolitical-driven cost pressures is eroding profitability more directly than anticipated. The company's new revenue streams from higher fares and ancillary fees are now in a race against these surging fuel costs, raising investor concerns about margin sustainability for the remainder of the year.