<P> A kickoff occurs at the start of each half and before each overtime (in the National and Arena Football Leagues). It is also traditionally decided by a coin toss at the beginning of each game carried out by the referee . The visiting team captain calls either heads or tails . The winner of the coin toss elects whether to take first choice in the first half or the second half . The captain with first choice then picks either a team to kick off or an end of the field to defend . The other captain chooses the remaining option . At the beginning of the second half, the two captains choose in the reverse order . If an overtime is required, another coin toss takes place to decide who gets first possession during the overtime . After a touchdown the scoring team kicks the ball off to the opposing team . In American football a field goal also results in a kickoff by the scoring team, but in Canadian football the scored - against team has an option of scrimmaging from their 35 - yard line or receiving a kickoff . </P> <P> If a team scores safety, the team that gave up the safety is required to kick the ball off from its own twenty - yard line, referred to as a free kick . Although this is not a requirement, most teams choose to punt the ball on the free kick (teams can also dropkick or placekick the ball); the National Football League, in contrast to most other leagues, prohibits the use of a kicking tee on a safety free kick . The same rules apply as on a normal kickoff, whereas the ball is a live ball if it travels at least ten yards without the receiving team fielding it . </P> <P> The line where the ball is placed for kickoff varies among the rule books . It is placed on the kicking team's 30 - yard line in six - man football, 35 - yard line in college and professional outdoor football, 40 - yard line in American high school football, 45 - yard line in amateur Canadian football, and the goal line in indoor and arena football . For the 2016 season only, the Ivy League placed the ball on the 40 - yard line in conference games . All players on the kicking team except the kicker (and, if used, a holder) must not cross the line at which the ball is placed until the ball is kicked . The receiving team must stay behind the line that is 10 yards from where the ball is placed . The ball can be fielded by the receiving team at any point after it has been kicked, or by the kicking team after it has traveled 10 yards or has been touched by a member of the receiving team . In American football (but not Canadian) touchback and fair catch rules apply to the kicked ball . If it is fielded by the kicking team, it is called an onside kick . A low, bouncing kick is called a squib kick . Although a squib kick typically gives the receiving team better field position than they would if a normal kick had been used, a squib kick is sometimes used to avoid giving up a long return, as well as use up a valuable amount of time on the clock, as it is impossible to fair catch such a kick . It is usually done when a team takes the lead in the final seconds, and is done to safely run out the remainder of the clock . Squib kicking with more than 20 seconds remaining has had unfortunate results (a line drive kick is more common when there are 20 to 50 seconds remaining; the typical hurry - up offense drive takes over a minute), but has been done by some teams . </P> <P> If a receiving player crosses his restraining line before the kick, the ball is to be advanced 5 yards, then re-kicked . If a kicking team player crosses the line at which the ball is placed before it is kicked, the receiving team has the option either to have the kicking team re-kick from 5 yards farther back, or have 5 yards added on to the end of the return . In high school football, the receiving team only has the option to make the kicking team re-kick . </P>

Where do you kick off from in nfl