Call the destination airport. If you know where the flight you're wondering about left (the departure airport), customer service representatives at the arrival airport should be able to tell you what the flight status is. It is best if you know the flight number before calling.
Check with the airline by phone or online. Most airline websites have a feature where customers can type in a flight number and get the status of the plane. Some airlines even give you the option of signing up for email or text alerts for flights.
Use a third-party site. The Track Flight Stats website allows you to type in an airline and flight number to find the status you are looking for.
Look around if you are already at an airport; it will have large boards throughout the facility that show every departure and arrival scheduled within a given period of time. Those boards will tell you if the flights are delayed or on time.
