Travelers line up wearing protective masks indoors at O'Hare International Airport in Chicago in December 2021. U.S. District Judge Kathryn Kimball Mizelle voided the national travel mask mandate on Monday.

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Travelers line up wearing protective masks indoors at O'Hare International Airport in Chicago in December 2021. U.S. District Judge Kathryn Kimball Mizelle voided the national travel mask mandate on Monday. / AP

Updated April 19, 2022 at 8:14 AM ET

U.S. airlines are lifting mask mandates, after a federal judge in Florida ruled against the Biden administration's mandatory mask mandate for travelers on planes and other public forms of transportation.

Monday's ruling quickly reshaped U.S. air travel, as a cascade of carriers from Delta and United to Southwest and American said masks are now optional for travelers aboard their aircraft.

The massive shift means many airline employees no longer have to wear masks — and won't have to enforce the rule on passengers. But airlines also warn that travelers should still bring a mask on their trip, to conform with the rules where they land, particularly for international flights.

Here's a rundown of where airlines stand:

Alaska Airlines

Masks are now optional for customers, but they should be patient with the change in policy. "Even as more pandemic protocols and policies ease, our team will remain vigilant and prepared for whatever may come next," the airline said. "Safety remains our top priority."

Alaska said it will be ready to respond if the U.S. is faced with another COVID-19 surge.

"Please remember to be kind to one another and that wearing a mask while traveling is still an option," the statement added.

American Airlines

American's mandatory mask requirement for travelers and staff at U.S. airports and on domestic flights is now rescinded.

Like other airlines, American said face masks may still be required in some places, based on local ordinances or when traveling to and from international locations.

Delta Air Lines

Masks are optional onboard, but Delta warned that travelers may encounter "inconsistent enforcement" over the first 24 hours as the news is being "broadly communicated."

"Communications to customers and in-airport signage and announcements will be updated to share that masking is now optional — this may take a short period of time," Delta said in its statement.

In a note of optimism about the pandemic, the airline added, "We are relieved to see the U.S. mask mandate lift to facilitate global travel as COVID-19 has transitioned to an ordinary seasonal virus."

Frontier Airlines

"To mask or not to mask, the choice is yours," the airline said.

It cautioned that passengers should still check the policies at their destination, noting that some airports or countries where Frontier flies might still require masks.

Hawaiian Airlines

Face masks are now optional for passengers and crew members on board flights, the airline said. "We advise travelers to stay informed and follow mask requirements that may remain in effect at their origin or arrival airports," it said.

JetBlue Airways

"While no longer required, customers and crewmembers are welcome to continue wearing masks in our terminals and on board our aircraft," JetBlue said.

Spirit Airlines

"We understand some Guests may want to continue wearing face coverings on flights, and that's perfectly fine under our optional policy," Spirit said.

Southwest Airlines

Southwest said it encourages passengers and employees to "make the best decision to support their personal wellbeing," and it will monitor public health guidance and federal requirements.

Southwest added that its cabin air ventilation systems use "HEPA air filtration that removes at least 99.97% of airborne particles."

United Airlines

Masks are no longer required on domestic flights and some international flights.

"While this means that our employees are no longer required to wear a mask — and no longer have to enforce a mask requirement for most of the flying public — they will be able to wear masks if they choose to do so, as the CDC continues to strongly recommend wearing a mask on public transit," the company said in a statement to NPR.

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