Jet fuel averaged $4.50 a gallon Thursday afternoon, topping September's all-time monthly high of $4.37 and setting the backdrop for a third-quarter earnings season in which record revenues will not translate into record profits.

The figures come from Argus Media data published by Airlines for America. September's average beat the previous record of $4.29 set in April. Prices have swung since the start of the Iran war and climbed again as fighting intensified.

Delta opens the season on Friday. Most carriers expect record top lines, but surging fuel costs are consuming most of those gains before they reach the bottom line.

Who makes money and who bleeds?

Deutsche Bank's October 5 note draws a hard line through the industry. Only four major U.S. carriers — Delta, United, Southwest, and Allegiant — appear likely to turn a profit this year.

The rest face red ink in 2026:

• American and JetBlue: potential pretax losses of roughly $1 billion each
• Alaska and Frontier: expected to lose money next year

For JetBlue, the projection extends a painful streak. The carrier has already posted six consecutive years of losses.

Fares are up 32% — but how much more will stick?

Average domestic airfare is up about 32% year over year, according to Kayak. That number is the central question for anyone selling air travel: carriers are testing the ceiling of what consumers will pay.

Melius Research analyst Conor Cunningham wrote that airlines now have to push price just as capacity growth picks up and consumer sentiment weakens. Another round of aggressive hikes, he warned, could test demand.

That tension matters for sellers. If pricing power breaks, carriers will respond with capacity cuts — already underway — that shrink inventory and force sellers to work harder for margin on fewer seats.

Premium is the escape hatch

Carriers are channeling their fuel problem into a cabin-class restructuring, and each move shifts what sellers can merchandise:

• United ordered more than 250 aircraft with expanded business class and premium economy
• Delta is revamping Delta One
• American is flying retrofitted 777-300ERs
• Alaska is expanding business class
• JetBlue is launching domestic first class to try to end its six-year losing run

The premium push is a distribution play as much as a product one. Higher fare buckets carry higher commissions and ancillary attach rates for agencies, while the basic-economy segment — where fees have risen alongside fares — grows harder to monetize.

Ancillary fees have risen across the board as carriers chase revenue outside the base fare, another margin lever that sellers must track when quoting total trip cost.

What's next for earnings season

The pattern to watch starting Friday is the gap between revenue records and profit guidance. Delta's numbers will show how much of the fare inflation reached the operating line; American's and JetBlue's outlooks will show whether Deutsche Bank's $1 billion loss scenario holds or proves too pessimistic.

With fuel volatile, capacity being trimmed, and Cunningham's demand warning hanging over further fare hikes, the carriers that profit will be those whose premium cabins and cost structures absorb fuel at $4.50 — not those betting consumers keep paying 32% more.