Hamas militants on Israel over the weekend, saying they were waiting for safety conditions to improve.
Israel's national carrier El Al was the exception, adding more flights to bring reservists back from around the world to assist in the country's biggest mobilization in history.
Fighters from the Islamist group killed 700 Israelis and abducted dozens in Saturday's attacks, the deadliest such incursion in decades, prompting Israel to retaliate by pounding the Palestinian enclave of Gaza.
Israel's tourism sector is set to take a major hit as flight cancellations pile up. Tourism makes up 3.6% of total employment in the country, according to OECD data.
Tourism bookings were 18% below pre-pandemic levels and had been rising earlier this year, according to travel data firm ForwardKeys.
Regulators including the United States' Federal Aviation Administration, the European Union Aviation Safety Agency and Israel's aviation authority urged airlines to use caution in the region's airspace, but stopped short of suspending flights.
Israel's civil aviation authority asked airlines to «review current security and threat information» amid the conflict, and changed some air traffic routes. It noted that delays were expected and advised airlines to carry extra fuel.
On Sunday, U.S. air carriers United Airlines, Delta Air Lines and American Airlines suspended direct flights following the FAA's caution advisories.
The U.S.