Puerto Rico is set to tighten its entry requirements for domestic U.S. travelers on Monday, amid one of the busiest travel periods of the year.
Starting Monday, all passengers arriving on domestic flights will need to show a negative coronavirus test taken no more than 48 hours before arrival, regardless of vaccination status. It wasn’t immediately clear what sort of tests are accepted; USA TODAY reached out to Puerto Rico’s destination marketing organization for more information.
Passengers who arrive without a COVID test will have 48 hours to take a test upon arrival, and face a $300 fine if they don’t get tested in time.
If unvaccinated, travelers will also need to quarantine seven days after arrival, even if they have a negative test.
Currently, only unvaccinated domestic travelers are required to show proof of a negative test.
Puerto Rico Gov. Pedro Pierluisi announced the rule change on Monday, just one week before the new rules were set to go into effect. The new testing requirement comes as the U.S. faces yet another testing shortage, with long lines at testing centers in places like New York City and retailers limiting testing kit sales.

This isn’t the only COVID rule change coming to the island amid the holiday travel season.
As of Wednesday, large indoor and outdoor events at venues like theaters and stadiums require proof of vaccination and a negative coronavirus test taken no more than 48 hours before the event.
And as of Monday, all establishments serving food or drink will require proof of vaccination or a negative test taken 48 hours before arrival.
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Follow USA TODAY reporter Bailey Schulz on Twitter: @bailey_schulz.