Do airlines allow AirTags with lithium batteries in checked luggage?

I'll be flying only domestically on American Airlines and United Airlines. I'll try to call one of them, but I'm afraid that I'll get a "no" from someone who's unfamiliar with the FAA regulation.

No need to call the airlines.

When asked if you have lithium batteries in your luggage, answer "no". They are asking about much larger lithium batteries in laptops, etc.

More info from American Airlines is here:

https://www.aa.com/i18n/travel-info/baggage/restricted-items.jsp

Click the Batteries link

Lots of car key fobs use CR2032 batteries. It would be entertaining to watch an airline try to tell a planeload of people they can't bring their car keys.

All I can say is people are placing AirTags in their luggage all over the world and there are hundreds of reports of people finding their lost luggage with AirTags when the airline stopped cooperating.

My Air Tag was removed today by Copa Airlines before my luggage was put on the plane from Cartagena, so it must have triggered their scanning system. When my name was called while waiting to board, they said something about a battery, but I thought it might have been a charger in my luggage. I didn’t realize til I got home that the Air Tag is still in Cartagena but my luggage made it. Just an FYI when traveling with smaller airlines.

Since they have lithium batteries, are they allowed by the airlines?

The FAA allows AirTags on U.S. flights. Most airlines in other countries do as well, but you would have to check with the airline to confirm.

That being said, most international travelers do not really check with the airline, and the airlines are aware of this.

https://www.travelersunited.org/can-air-travelers-use-apple-for-luggage-tracking/#:~:text=%E2%80%9CLuggage%20tracking%20devices%20powered%20by,luggage%20tracking%20devices%20may%20not.%E2%80%9D

to get full verification you would probably have to contact the airline, but CR2032 Batteries is not some exotic rare battery it's used in great many things that people may wish to bring when they travel