According to CNN Travel, here is the most current list of international destinations that are open to U.S. citizens, both with and without restrictions.
Open to U.S. citizens:
Albania
Belarus
Brazil
Mexico
North Macedonia
Serbia
Turkey
Zambia
Open with restrictions to U.S. citizens:
Antigua and Barbuda
Negative Covid-19 test result within 7 days
Armenia
Negative Covid-19 test at airport or 14-day mandatory quarantine
Aruba
Negative According to CNN Travel, here is the most current list of international destinations that are open to U.S. citizens, both with and without restrictions.
Barbados
Negative Covid-19 test result within 72 hours
Bermuda
Negative Covid-19 test result within 5 days + $75
Cambodia
Negative Covid-19 test result within 72 hours + $2,000 Covid-19 deposit
Costa Rica
Negative Covid-19 test result within 48 hours, travel insurance and health form
Croatia
Negative Covid-19 test result within 48 hours
Dominica
Negative Covid-19 test result within 72 hours
Dominican Republic
Negative Covid-19 test result within five days
Dubai
Negative Covid-19 PCR test result within 96 hours of arrival, travel insurance and health form
Ecuador
Mandatory 14-day quarantine and negative Covid-19 test result within 7 days
Egypt
Negative Covid-19 test result within 72 hours
Ethiopia
Negative Covid-19 test result within 72 hours, 14-day quarantine
French Polynesia
Negative Covid-19 test result within 72 hours
Ghana
Negative Covid-19 test result within 72 hours
Grenada
Negative Covid-19 rapid result test result on arrival
Haiti
Mandatory 14-day quarantine
Honduras
Negative Covid-19 rapid result test result on arrival
Ireland
Self-isolate for 14 days
Jamaica
Negative Covid-19 test result less than 10 days old
Kenya
Negative Covid-19 test result within 96 hours
Maldives
Negative Covid-19 test result within 72 hours
Malta
Must transit through a safe corridor country after staying 14 days in that country
Montenegro
Negative Covid-19 test result within 72 hours
Namibia
Negative Covid-19 test result within 72 hours, mandatory 7-day quarantine
Rwanda
Negative Covid-19 test result within 120 hours of departure
South Korea
Mandatory 14-day quarantine
St. Barts
Negative Covid-19 test result within 72 hours
St. Lucia
Negative Covid-19 test result within 7 days
St. Maarten
Negative Covid-19 test result within 72 hours
St. Vincent and Grenadines
Negative Covid-19 test on arrival, additional test on arrival
Tanzania
Covid-19 tests on arrival
Turks and Caicos
Negative Covid-19 test result within 5 days
United Kingdom
Self-isolate for 14 days
Source: CNN Travel
