In the NFL, the coin toss takes that takes place before the game determines which team will receive the ball. A team can choose the ball, or can defer the ball and chose a side of the field.
The coin toss takes place on the 50-yard line, and includes the head referee and 3 to 6 captains from each team. When applicable, ceremonial guests may also be present.
The coin to be tossed is showed to both teams, and the visiting team calls the coin--heads or tails--once it is in the air, flipped by the head referee. The referee then allows the coin to reach the ground to determine the outcome.
At the beginning of overtime, the team captains will again convene to call the coin toss at midfield. It is again the visiting team's call; the winner of this coin toss selects to receive the ball an overwhelming majority of the time.
Because of a botched coin flip call during the 2001 season, the referee has to confirm the call made by a player before the coin lands.
The coin toss must take place within 3 minutes of kickoff of both the beginning of the game and of overtime.
Though there is no coin flip before the second half, the loser of the opening coin flip decided between the ball and which side of field their team is to defend. Most often, this team selects to receive the ball.