Austria
Rules on boosters: Austria requires travelers have their COVID-19 booster shot if 270 days have passed since their last vaccine. Travelers who have their booster shot are also exempt from a pre-arrival PCR test. Travelers who have not received a booster shot must show proof of a negative PCR test taken within 72 hours.
What else is needed to enter: Alternatively, Austria allows travelers who show proof they contracted COVID-19 and recovered to enter the country with a PCR test. Travelers who are fully vaccinated and show proof of recovery are exempt from the PCR test. Children under 12 are also exempt from showing proof of vaccination or a negative test if they are accompanied by a fully vaccinated or recovered adult.
Proof of vaccination or recovery is required in Austria to visit hotels, restaurants, cultural institutions, ride ski lifts, and more.
Find out more about Austria's travel requirements here.
Croatia
Rules on boosters: Croatia requires a booster dose for anyone who received their initial vaccine shots more than 270 days ago. Unvaccinated travelers can also enter by showing proof of a negative PCR test taken within 72 hours of arrival, proof of a negative rapid antigen test taken within 24 hours of arrival, or proof they contracted COVID-19 and recovered within the past 180 days.
What else is needed to enter: All tourists must show a certificate of reservation or paid accommodation while in Croatia.
Find out more about Croatia's travel requirements here.
France
Rules on boosters: All travelers 18 and older who have been vaccinated for more than 9 months will need a booster shot to enter.
What else is needed to enter: Travelers also need to show proof of a negative PCR or antigen test taken within 48 hours of their departure. Visitors will also need to download a digital certificate to enter places like restaurants and cafes as well as travel on long-distance trains.
Find out more about France's entry requirements here.
Greece
Rules on boosters: Greece does not require American travelers to be boosted to enter the country, but does require proof of vaccination to access places like indoor restaurants. For this purpose, a vaccine is valid for 7 months and travelers must receive a booster to remain valid after that time period.
What else is needed to enter: All U.S. travelers must arrive with proof of a negative COVID-19 PCR test taken within 72 hours of their arrival or a negative rapid antigen test taken within 24 hours of their arrival.
Find out more about Greece's entry requirements here.
Iceland
Rules on boosters: Iceland welcomes vaccinated travelers without restrictions, but requires them to be boosted if it has been more than 270 days since the final shot of their initial vaccination series.
What else is needed to enter: Travelers must show proof of a negative COVID-19 PCR or antigen test taken within 72 hours of their departure for Iceland. Travelers who have contracted COVID-19 and recovered within the past 180 days are exempt from the pre-arrival test.
Find out more about Iceland's entry requirements here.
Israel
Rules on boosters: Israel requires travelers to have recieved a booster shot if 180 days have passed since their initial vaccine series. Travelers must also be fully vaccinated with two doses of the Pfizer or Moderna vaccine or one dose of the Johnson & Johnson vaccine within six months of travel. Israel was one of the first countries to implement a booster requirement.
What else is needed to enter: All vaccinated international tourists must also show proof of a COVID-19 PCR test taken within 72 hours or a rapid antigen test taken within 24 hours before their flight, and get tested with another PCR test upon arrival.
Find out more about Israel's entry requirements here.
Netherlands
Rules on boosters: The Netherlands requires a booster dose for vaccinated travelers who received the final dose of their initial vaccine series more than 270 days before their trip. Travelers who received a booster dose at least seven days before their trip are not required to self-quarantine upon arrival.
What else is needed to enter: Travelers must also show proof of a negative COVID-19 PCR test taken within 48 hours of their departure or a negative antigen test taken within 24 hours of their departure.
Find out more about the Netherlands' entry requirements here.
Spain
Rules on boosters: To enter the country, Spain requires international travelers from the U.S. to show proof they are vaccinated and have received a booster dose if more than 270 days have passed since the final dose of their initial vaccine series.
What else is needed to enter: Travelers must also fill out a Spain Health Control form, which can be obtained through the Spain Travel Health portal or through apps on Android or iOS devices.
Find out more about Spain's entry requirements here.
Switzerland
Rules on boosters: American travelers can enter Switzerland if they have been fully vaccinated within the past 270 days. If it has been more than 270 days since the final dose of their initial vaccination series, they must be boosted.
What else is needed to enter: Vaccinated travelers have to fill out an entry form, but are exempt from pre-arrival testing.
Find out about Switzerland's entry requirements here.