Current Phone Call Ban
The FCC has banned cell phone calls on commercial flights in the United States since 2013. This means you cannot make or receive traditional phone calls while flying. Airlines enforce this rule as part of their onboard policies. If a phone receives a signal during flight, it is against regulations to use it for voice calls.
Why Calls Are Banned
Phone calls are banned primarily to protect the comfort and safety of all passengers. Allowing phone conversations would create noise and disruptions in the airplane cabin where hundreds of people are sitting closely together. The ban also helps prevent potential safety issues and allows flight attendants to communicate with passengers more effectively.
Airplane Mode and WiFi Use
The FCC requires all mobile phones to be switched to airplane mode before takeoff. This disables the phone's ability to connect to cellular networks. However, many modern aircraft have WiFi service where passengers can use internet-based messaging and email. Some airlines allow WiFi calling through certain apps, while others block these services entirely.
What You Can Do Instead
Passengers can send text messages, emails, and use messaging apps like WhatsApp or iMessage over WiFi on many flights. Some airlines offer WiFi packages specifically for this purpose. Once the flight lands, you can use your phone normally again when it is safe to do so according to crew instructions.
International Flights
The ban on phone calls during flight applies to flights within U.S. airspace and on U.S. airlines. Some international airlines may have different policies, but most major carriers worldwide also prohibit voice calls to maintain passenger comfort across the global aviation system. 
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