Flight cancellations were again worsening on Monday as air traffic controller shortages worsened by the longest-ever U.S. government shutdown snarled air travel coast to coast.

Air traffic controllers on Monday missed their second paycheck of the shutdown, though they are still required to work. Some of them have taken second jobs to make ends meet, government and union officials have said.

A sign of how severe air travel disruptions have become in the government shutdown: Sunday’s 2,631 U.S. flight cancellations, 10% of the schedule, marked the 4th worst day since January 2024, according to aviation-data firm Cirium.

In comparison, on Friday morning, as Trump administration-mandated flight cuts took effect, cancellations ranked 72nd since the start of last year.

The Senate made progress overnight on a deal that could end the shutdown, but it has not yet approved a funding bill.

On Monday, 1,432 of the 25,733 scheduled flights across the country were canceled, around 5.5% “and growing,” Cirium said. Disruptions piled up over the weekend, with 18,576 flights delayed and 4,519 canceled, according to FlightAware.

Cancellations spilled over from regional, short-haul jets — which the largest U.S. airlines rely on for around half of domestic flights — to mainline flying.

United Airlines and Delta Air Lines were each offering flight attendants extra pay to pick up flights, according to company messages seen by CNBC. The airlines didn’t immediately comment. Such extra pay is common during storms or other disruptions.

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