Yes, American Airlines has made sure that you travel safely. That is why you need to show your Covid test before you board the flight, including that it is also mandatory to follow the safety measures in the flight. In that manner, you're going to travel very safely. You would need to show the Covid test, which you took one day before the flight's departure. That means an older test is not going to work. 

Covid guidelines of American Airlines: 

In case you are wondering, "Does American Airline require Covid test?" Then you can follow the information regarding Covid below. 

Covid test and the Vaccine requirements:

For the US citizens - 

Attestation is mandatory on the test report. 
The Covid test must have been taken within one day of the flight's departure date. 
For the Non-US citizens-

You would need to show proof of both the vaccinations you have taken. For that, you need to share the mandatory certificate. 
You also need to show the Covid test report. That will prove that you're not suffering from Covid and you can travel on the flight of American Airlines. Make sure that the test is not more than one day old. 
General guidelines of American Airlines regarding the Covid:

 Children who have there age below two years. They are not going to require any Covid test. That means if you're traveling with an infant, then you should not be worrying about the Covid test. 
Vaccination is not required for passengers below eighteen years. However, they would need to show the Covid test reports. 
In case you want any further details. Then you can connect with American Airlines customer service. After that, you're not going to face any issues. 

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