The Biden administration will lift travel restrictions starting in November on foreigners who are fully vaccinated against the coronavirus, reopening the country to thousands of people, including those who have been separated from family in the United States during the pandemic.

The foreign travelers will need to show proof of vaccination before boarding and a negative test for the coronavirus within three days before coming to the United States, Jeff Zients, the White House pandemic coordinator, said Monday.

“International travel is critical to connecting families and friends, to fueling small and large businesses, to promoting the open exchange ideas and culture,” Mr. Zients said. “That’s why, with science and public health as our guide, we have developed a new international air travel system that both enhances the safety of Americans here at home and enhances the safety of international air travel.”

The administration has restricted travel for foreigners looking to fly to the United States from a group of European countries, Iran and China for more than a year.

Unvaccinated Americans overseas aiming to travel home will have to clear stricter testing requirements. They will need to test negative for the coronavirus one day before traveling to the United States and show proof that they have bought a test to take after arriving in the United States, Mr. Zients said. The Centers for Disease Control and Prevention will also soon issue an order directing airlines to collect phone numbers and email addresses of travelers for a new contact-tracing system. Authorities will then follow up with the travelers after arrival to ask whether they are experiencing symptoms of the virus.

The changes announced on Monday only apply to air travel and do not affect restrictions along the land border, Mr. Zients said.