The U.S. Is Reopening. Here’s What Travelers Need to Know About Testing, Boosters and More.

On Nov. 8, the United States will lift an 18-month ban on international tourists, as long as they show proof of vaccination and a negative coronavirus test. The land borders with Canada and Mexico will also reopen for international visitors who are fully vaccinated and American citizens residing in those countries, as well as U.S. tourists returning home. Currently, passenger traffic in the United States is close to reaching 2019 levels, with millions of domestic travelers passing through Transportation Security Administration checkpoints each day.

Millions more are expected to hit the skies and the roads in the coming weeks. But as pandemic regulations ease in some countries, others are tightening entry rules to contain new waves of the virus. The shifting rules, rapidly changing course of the pandemic and lack of international coordination on travel regulations continue to leave consumers — and many travel operators — flustered and confused.

Travelers, both those going abroad and those entering the United States, are likely to have questions about the complicated regulations this holiday season. Here’s what we know so far, but be sure to come back — as rules are constantly changing.

Where can I find a test to get into the United States?

Both PCR and viral tests are accepted for travel to the United States. Vaccinated travelers must take the test 72 hours before their departure, while unvaccinated American travelers must take the test within 24 hours.

Many hotels offer in-house testing facilities for an additional fee. If not, ask the concierge service or hotel reception for the nearest place you can get tested that will guarantee results within the required time frame.

Many pharmacies offer tests for travel and most major cities have walk-in test sites, which do not require appointments. Test prices can vary between $25 and $150, depending on the country and PCR tests are more expensive and results take longer to process.

As a fallback, most airports offer coronavirus testing, but expect to pay a hefty price and lines could be long, so make sure to go early.

What about a self-test, is that accepted?

Yes, as long as the test meets several requirements. It must be an antigen or nucleic acid amplification test that has been approved for emergency use by the Food and Drug Administration.

Make sure you have a good internet connection when you take the test because you will have to connect to a telehealth service that verifies your identity and provides supervision during testing.

The F.D.A. has authorized eight home-tests, but not all of them provide digital supervision and prompt results.

The Abbott’s BinaxNOW Covid-19 AG Card Home Test usually produces results within 15 minutes and comes with a digital app calledNAVICA, which can be helpful for travel as it facilitates easier access to results. Once you receive a negative test result, the app will generate a QR code that is renewed each time you take a new test.

How much does a rapid-self test cost?

A six-pack of the BinaxNow tests costs $150 and can be purchased online at eMed. Packs of two home tests are also available at select pharmacies for around $25.

The Ellume home test, another popular option for international travel, costs between $30 and $40. The home-tests are in high demand, so make sure to order them well in advance of your trip.

Will I need a digital vaccine certificate to travel?

While most countries accept the white paper C.D.C. vaccination card, some places, like the Cayman Islands, require digital certificates and impose quarantine restrictions on people who are unable to provide them.

There are several digital health passes in the United States that are convenient for travel, but make sure you check country-specific requirements before your departure. The Smart Health Card is a verifiable digital proof of vaccination that generates a QR code, which only shows the individual’s name, date of birth and vaccination status. It can be obtained in states using the Smart health system or through the retail pharmacy program.

Healthpass by Clear is another option that generates a QR code and vaccination details, including the type and number of shots received. Clear has partnered with the Hawaii Safe Travel program, and provides verification of a passenger Covid-19 test results or proof of vacation to satisfy the state’s quarantine exemption requirements. The app allows visitors to skip the verification line upon arrival in the state.

Several states, like New York and California, have their own digital apps, which pull data from the state’s immunization registry and can be used for travel.

While most countries will accept the digital passes for entry, some require visitors to apply for local digital passes to secure access to restaurants, bars, and cultural activities. Switzerland was one of the first countries to adopt this measure last month, requiring all tourists from outside the European Union and Schengen Area to register for a Swiss health pass before arrival.

Are booster shots necessary for international travel?

For most places, not yet. But as new coronavirus variants emerge and concerns grow over waning vaccine efficacy, some countries are setting vaccine “expiration dates” for travelers.

Croatia and Austria were among the first countries to introduce the expiration dates this summer, only accepting second vaccine doses or booster shots administered within a year of entering the county. For those who have received the one-dose Johnson & Johnson vaccine, the validity period is 270 days, around 9 months. Anyone who does not meet the criteria also has the option to submit a negative coronavirus test taken within 72 hours before departure.The United States does not have an “expiration date.”

Israel took a more stringent approach when it reopened to fully vaccinated foreign travelers on Nov. 1, only accepting vaccines that have been taken within the last six months.

Many countries say they are open to fully vaccinated travelers, but as booster shots roll out around the world, it is important to read the fine print to understand which vaccines are accepted and how long they are valid for.

Will I have to show proof of vaccination to fly domestically?

No. As of Nov. 8., only those entering the United States from abroad will have to show a vaccination certificate and proof of a negative coronavirus test taken within 72 hours before departure. Unvaccinated U.S. travelers are permitted to travel, but upon returning must present a coronavirus test taken within 24 hours of departure.

Masks continue to be required for domestic air travel.

Do my children need to be vaccinated to travel internationally?

Every country has its own entry requirements, so first check the policy for your destination. Unvaccinated children under the age of 18 are permitted to enter the U.S. if they are over the age of 2, are traveling with a vaccinated adult and have taken a coronavirus test with negative results three days before departure. If a child is traveling alone or with an unvaccinated adult, they will have to test within 24 hours of travel.

Are the rules different at land border crossings?

As of Nov. 8, the U.S. land borders with Canada and Mexico will reopen for fully vaccinated foreign nationals. While visitors will need to show proof of vaccination, there is no testing requirement for land-border crossings. Children under the age of 18 are allowed entry ifaccompanied by a vaccinated adult.

I’m an American citizen. Where can I find rules for entering other countries?

The Times keeps an updated list of countries where Americans can currently visit with details of specific entry requirements.

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