Investing.com -- US airline fuel expenses climbed to nearly $6.5 billion in April, marking a 78% increase from the same month last year, according to data released by the US Transportation Department on Monday. The rise stems from elevated jet fuel prices linked to ongoing conflict in the Middle East.

The department's monthly report showed fuel costs rose 26% compared to March, while airlines reduced fuel consumption by 2.6% during the same period. Jet fuel prices reached $4.11 per gallon in April, up $1.81 from April 2025.

The price increases have affected carriers across the industry. Spirit Airlines, a budget carrier, stopped operations in May, citing unsustainable fuel costs as the primary reason for the shutdown.

Delta Air Lines, United Airlines, American Airlines, and Southwest Airlines operate approximately 80% of domestic flights in the US.

The International Air Transport Association released its annual report on Sunday, projecting the global airline industry will generate a combined net profit of $23 billion in 2026. The forecast represents a reduction from the group's earlier estimate of $41 billion and a decline from $45 billion in 2025. The association represents over 370 airlines that handle about 85% of worldwide air traffic.

Flight prices have increased for US-origin travel this year, with domestic fares rising as much as 31% and international fares climbing up to 22% compared to the same periods in 2025, based on KAYAK search data.