American football rules Game play in American football consists of a series of " downs " , individual plays of short duration , outside of which the ball is " dead " or not in play . These can be plays from scrimmage — passes , runs , punts , or field goal attempts — or free kicks such as kickoffs . Substitutions can be made between downs , which allows for a great deal of specialization as coach es choose the players best suited for each particular situation . During a play , each team should have no more than 11 players on the field , and each of them has specific tasks assigned for that specific play . Objective of the game . The objective of this game is to score more points than the opponent during the allotted time . Points are scored as long as one of the teams controls the ball . The team with the ball ( the " offense " ) has 4 tries ( " downs " ) to advance at least 10 yards , and can score points once they reach or near the opposite end of the field , called the " end zone " . If the offense does not advance at least 10 yards during their 4 downs , the team without the ball ( the " defense " ) regains control of the ball ( called " turnover on downs " ) . On offense , points are scored by advancing the ball into the opponent ' s end zone for a " touchdown " ( worth six points ) , or by kicking the ball from the playing field through the raised vertical posts ( the " goal posts " ) in the back of that end zone for a " field goal " ( worth three points ) . After scoring a touchdown , the offense is given one additional play from the 2 yard line ( 3 yard line in amateur football ) to attempt to score . These attempts are termed " point after touchdown " ( PAT ) and are used to score 1 or 2 points as follows : While the opposing team has possession , the defense attempts to prevent the offense from advancing the ball and scoring . If an offensive player loses the ball during play ( a " fumble " ) or the ball is caught by a defensive player while still in the air ( an " interception " ) , the defense may attempt to run into the offense ' s end zone for a touchdown . The defense may also score points by tackling the ball carrier in the offense ' s own end zone , called a " safety " ( which is worth two points ) . Time of play . Collegiate and professional football games are 60 minutes long , divided into four quarters of 15 minutes each . In high school football , 12 minute quarters are usually played . The clock is stopped frequently , however , so that a typical college or professional game can exceed three hours in duration . The referee controls the game clock and stops the clock after any incomplete pass or any play that ends out of bounds . In addition , each team is allowed 3 timeouts in each half that they may use at their own discretion . The clock may also be stopped for an officials ' time - out , after which , if the clock was running , it is restarted . For example : if there is a question as to whether or not a team has moved the ball far enough for a first down , the officials may use a measuring device ( " the chains " ) to determine the distance . While this measurement is taking place , the officials will signal for a stoppage of the clock . Once the measurement is finished and the ball is placed at the proper location ( " spotted " ) , the referee will then signal for the clock to restart . Additional situations where officials may take a time - out are to administer a penalty or for an injured player to be removed from the field . In addition to the game clock , a separate " play clock " is also used . This counts down the time the offense has to start the next play before it is assessed a penalty for delay of game ( see below ) . This clock is typically 25 seconds from when the referee marks the ball ready for play . The NFL and NCAA use a 40 - second play clock that starts immediately after the previous play ends , though for certain delays , such as penalty enforcement , the offense has 25 seconds from when the ball is marked ready . The purpose of the play clock is to ensure that the game progresses at a consistent pace , preventing unnecessary delays . Officials also call for media time - outs , which allow time for television and radio advertising . They also stop the clock after a change of possession of the ball from one team to the other . Successful PATs ( Point ( s ) After Touchdown ) , a field goal try , or a kickoff may also warrant stopping the clock . If an instant replay challenge is called during the game , the referees signal for a media time out . The referee signals these media time - outs by first using the time out signal , then extending both arms in a horizontal position . Separating the first and second halves is " halftime . " Teams change ends of the field at the end of the first quarter and the end of the third quarter . In the NFL , an automatic timeout is called by the officials when there are two minutes left in both the second and the fourth quarters , and overtime ; this is most commonly referred to as the " two - minute warning . " No such warning is normally given in amateur football , though if there is no visible stadium clock , the referee will give a two - minute warning ( four minutes in high school ) . Overtime . If a game is tied at the end of four quarters , " overtime " is played . During the regular season in the NFL , one overtime period is played ( with each team receiving two time outs ) , and each team receives one possession to score , unless one of them scores a touchdown on its first possession . Sudden death rules apply if both teams have had their initial possession and the game remains tied . If both teams are tied after the 15 - minute overtime , the game officially ends in a tie . Overtime follows a three - minute intermission after the end of the regulation game . Prior to start of overtime , a coin flip is performed where the captain of the visiting team calls the toss . The team that wins the coin flip has the option to either receive the kickoff or choose the side of the field they wish to defend . Ties are rare in the NFL ; the game between St . Louis and San Francisco on November 11 , 2012 ended in a 24 - all tie , the first tie since 2008 . Beginning in the 2010 NFL post - season , a modified sudden - death system for overtime games was put into effect . The overtime rules were changed to reduce the apparent advantage gained by the team that won the overtime coin toss . Under the prior rules , the team that won the coin toss would usually elect to receive the ball , then gain just enough yardage to win the game by kicking a field goal without the other team ever touching the ball . The modified rules allow both teams to have the " opportunity - to - possess , " with one exception . The exception occurs if Team ( A ) scores a touchdown ( not just a field goal ) on their initial possession in overtime , then the game is over and Team ( A ) wins . But if a touchdown is not scored on Team ( A ) ' s opening drive , or if they score only a field goal , then Team ( B ) is given an opportunity to possess the ball by either a punt , a kick , or by taking over on downs from Team ( A ) . Of course , Team ( B ) could also gain possession by an interception or fumble from Team ( A ) . Once the requirement for " opportunity - to - possess " has been satisfied by both teams then normal sudden - death rules apply , meaning that the next team to gain more points than the other team wins the game ( note that it ' s possible for a tie score to occur during overtime play under these rules ) . Various events may occur that constitute " opportunity - to - possess " even though a team may not gain full possession of the ball in order to run a play . For example , if Team ( B ) muffs a kickoff or punt return ( i . e . , drops the ball while attempting to catch it ) which is then recovered by the kicking Team ( A ) , then Team ( B ) is considered to have had their " opportunity - to - possess , " and normal sudden - death rules would then be in effect . Similar to normal overtime , following a three - minute intermission after the end of the regulation game , a coin flip is performed wherein the captain of the visiting team calls the toss . However , in post - season overtime , multiple 15 - minute overtime periods may be played until a winner is declared . The first post - season overtime game played under the new overtime rules occurred in the 2011 - 2012 NFL AFC Wildcard Playoff game between the Denver Broncos and Pittsburgh Steelers at Sports Authority Field at Mile High , Denver , Colorado . Denver won the game on the first play in overtime , an 80 - yard touchdown pass from Tim Tebow to Demaryius Thomas . NFL Europa , a defunct league run by the NFL , used a 10 - minute overtime period , with the constraint that each team must have the opportunity of possession ; once both teams have had such an opportunity , the overtime proceeds in a manner similar to the NFL ' s . Thus , if Team A has the first possession of overtime and scores a touchdown and converts their kick ( thus being 7 points ahead of Team B ) , Team A would then kick off to Team B ( In the NFL , the game would have ended with the touchdown , without a conversion being attempted ) . Team B would have to match or exceed the 7 point difference within this ensuing possession ; exceeding it would end the game immediately , while matching the difference would result in a kickoff to Team A . From this point , the overtime is sudden death . The new United Football League also uses this rule . The defunct World Football League , in its first season of 1974 , used an overtime system more analogous to the system long used in international soccer . The overtime consisted of one 15 - minute period , which was played in its entirety and divided into two halves of 7½ minutes each , with each half starting with a kickoff by one of the teams . The league changed to the NFL ' s sudden - death format for its second and last season in 1975 . In college and high school football , an overtime procedure ( the " Kansas plan " ) ensures that each team has equal opportunity to score . In college , both teams are granted possession of the ball at their opponents ' 25 yard - line in succession . A coin flip takes place , with the winning team having the option either 1 ) to declare that they will take the ball first or second , or 2 ) to decide on which end of the field the series will occur ( both teams ' series occur on the same end of the field ) . The losing team will have the first option in any subsequent even - numbered overtime . In the first overtime , the team with first series attempts to score either a touchdown or a field goal ; their possession ends when either a touchdown or a field goal have been scored , they turn the ball over via a fumble or an interception , or they fail to gain a first down . After a touchdown , a team may attempt either an extra - point or a two - point conversion . However , if the team on defense during the first series recovers a fumble and returns it for a touchdown , or returns an interception for a touchdown , the defensive team wins the game . ( This is the only way for a college overtime game to end without both teams having possession . ) Otherwise , regardless of the outcome of the first team ' s series ( be it touchdown , field goal , or turnover ) , the other team begins their series . If the score remains tied after both teams have completed a series , a second overtime begins . If the score remains tied after two overtimes , teams scoring touchdowns are required to attempt a two - point conversion from the third overtime on . Just as in regulation , if a defensive team recovers a fumble / returns an interception to the end zone during a two - point conversion attempt , they will receive two points . In high school football in a majority of states , each team is granted possession of the ball at the 10 - yard line , meaning that a team cannot make a first down without scoring except via a defensive penalty that carries an automatic first down ( such as defensive pass interference or roughing the passer ) . As is the case with the college overtime rule , the team that wins the coin toss will have the choice as to whether to take the ball first or second , or decide at which end of the field the overtime will be played . The other major difference between overtime in college football and high school football is that in high school football , if the defense forces a turnover , they may not score . However , in Texas , the college overtime rule is used , as both the University Interscholastic League , which governs interscholastic activities for Texas public high schools , and the Texas Association of Private and Parochial Schools , the largest analogous body for Texas private high schools , play by NCAA football rules with a few modifications for the high school level . The defunct XFL used a modified Kansas Plan which , upon the first team scoring , required the opponent to score the same or greater amount of points in the same or fewer downs ( i . e . if the first team scored a touchdown , and converted the one - point conversion in three downs , the opponent would have to match that touchdown and conversion in three downs as well ) . Each team started at the 20 - yard line , but like high school , there were no opportunities for first downs . The league also banned field goals except for on a fourth down . Playing the game . Coin toss . Three minutes before the start of the game , the referee meets with captains from both teams for a coin toss . The visiting team calls the toss . The winner of the toss may defer their choice to the start of the second half , or they may take first choice of : The loser of the toss gets the remaining option . At the start of the second half , the team that did not choose first ( either because they deferred their choice or because they lost the toss ) gets the first choice of options . According to " USA Today " , in college games , the team that wins the toss defers their choice to the start of the second half over 90 % of the time . If a game goes to overtime , a coin toss is held before the start of overtime , but tosses are not held before the start of subsequent overtime periods . In college , for example , the loser of the toss to start overtime has first choice in the second overtime period . The choices available to the captains in overtime vary among the NFL , college , and various states ' high school rules . In high school , the coin toss may be held between the captains or coaches earlier before the start of the game . At three minutes before kickoff , the captains meet for a simulated coin toss , where the referee announces the results of the earlier toss . Downed player . A player carrying the ball ( the runner ) is downed when any of the following occurs : Scrimmage downs . The majority of a football game takes place on plays , or " downs " , that begin at the line of scrimmage . The officials " spot " the ball ( place it in a designated spot on the field ) on the line of scrimmage and declare it ready for play . Positions . The width of the spotted football defines the width of the neutral zone , an area of the field no player other than the snapper may position himself in or above before the snap . Each team has its own line of scrimmage , thought of as a vertical plane from sideline to sideline that passes through the point of the ball nearest its own goal line . The players on offense must arrange themselves in a formation , all behind their line of scrimmage ( that is , on their side of the ball ) . For reasons of safety and competitive balance , there are strict rules which define the way in which the offensive players may line up . Seven players must line up directly on the line of scrimmage , these are collectively referred to as " linemen " . Four players line up behind the line of scrimmage , these are collectively referred to as " backs " . Within this formation , there are six eligible receiver s who may receive a forward pass during play . These eligible receivers are the four backs , and the two players at either end of the line . The remaining five linemen , often called " interior linemen " do not normally handle the ball during a play . Because of these rules , various leagues of American football have enacted strict rules of uniform numbering so officials may more easily judge which players were eligible and which were not at the start of a play . For example , in college football , ineligible players wear numbers 50 - 79 , while eligible receivers wear 1 - 49 or 80 - 99 . Even within this structure , offenses can still present a wide number of formations , so long as they maintain the " seven and four " arrangement . Ends , for example , may play close to the other linemen ( called tight end s ) or they may play some distance down the line of scrimmage , where they are called split end s , or sometimes wide receiver s . Of the four backs , they may play behind the linemen , or may play " split out " to provide additional wide receivers . These additional receivers can be flanker s ( if they play split far wide , but still in the backfield ) or slot receiver s if they play in the " slot " between the split end and the rest of the offensive line . One of the four backs receives the snap from the center . This player is called the quarterback . The remaining members of the backfield are called a variety of names , depending on their intended role , such as running back , halfback , fullback , H - back , wingback , or slotback . The players on defense may arrange themselves in any manner , as long as all players are " behind the line " ( that is , on the side of the line nearest their own end zone ) . Players who line up opposite the offensive line are called defensive linemen , usually with one or two defensive tackle s in the middle ( a single defensive tackle is often called the nose guard or nose tackle ) and with one defensive end on each side . Behind the linemen are the linebackers . Positioned opposite the wide receivers are the cornerback s . Farthest back from the line are the safeties , usually in the middle of the field behind the linebackers . The linemen and linebackers , close to the line of scrimmage , are often referred to as playing " in the box " , players outside " the box " ( usually cornerbacks and safeties ) are collectively referred to as the " secondary " . Starting the down . A scrimmage down begins with a " snap " , where the center throws or hands the ball backward to one of the backs , usually the quarterback . The down ends when the ball becomes dead ( see below ) . The ball is typically next spotted where the ball became dead ; however , if it became dead outside the hash marks , it is brought in on the same yard line to the nearest hash mark . This spot becomes the line of scrimmage for the next play . In the case of an incomplete forward pass , the ball is returned to the spot where it was snapped to begin the previous play . A fumbled ball that goes out of bounds is declared dead and possession remains with the team that most recently had control of the ball . Dead ball . The ball becomes dead , and the down ends , when : The nearest official typically blows his whistle after the ball becomes dead to alert the players that the down has already ended . If the ball is alive and the official sounds an " inadvertent whistle " , then the ball still becomes dead , but the team in possession of the ball may elect to have the down replayed or take the spot where the ball was declared dead . If the ball was loose from a fumble , then the ball can be put into play at the spot of the fumble . If the ball was in flight from a kick or a pass , then the down is always replayed . Free kick downs . A free kick is a down which does not occur from scrimmage . The kicking team begins behind the ball , while the receiving team must remain at least 10 yards downfield before the ball is kicked . Kickoffs . A kickoff is a type of free kick where the ball is placed on a tee ( or held ) at the kicking team ' s 30 - yard line ( 40 for high school ) . In the 2011 NFL Season , changes were made regarding kickoffs to limit injuries . Kickoffs were returned from the 30 - yard line to the 35 - yard line , repealing a 1994 rule change . In addition , players on the kickoff coverage team cannot line up more than 5 yards behind the kickoff line , minimizing running starts and thus reducing the speed of collisions . The kicking team ' s players may not cross this line until the ball is kicked ; members of the non - kicking ( or " receiving " ) team are similarly restrained behind a line 10 yards further downfield ( the 40 - yard line , or 50 for high school ) . A valid kickoff must travel at least this 10 - yard distance to the receiving team ' s restraining line , after which any player of either team may catch or pick up the ball and try to advance it ( a member of the kicking team may only recover a kickoff and may not advance it ) before being downed ( see " Downed player , " below ) . In most cases , the ball is kicked as far as possible ( typically 40 to 70 yards ) , after which a player of the receiving team is usually able to secure possession ( since the members of the kicking team cannot start downfield until after the ball is kicked ) . Occasionally , for tactical reasons , the kicking team may instead choose to attempt an onside kick , in which the kicker tries to kick the ball along the ground just over the required 10 - yard distance in such a manner that one of his own teammates can recover the ball for the kicking side . If it is touched before ten yards , the ball is dead and a re - kick or spot of the ball will be rewarded to the receiving team . Receiving a kickoff . A member of the receiving team gaining possession of the ball on a kickoff may attempt to advance it as far as he can toward the kicking team ' s goal line before being downed . Once the ball carrier is downed , the play is whistled dead and the ball is placed by the officials at the point where the play ended ; this spot then becomes the line of scrimmage for the ensuing play . A kick that travels through or goes out of bounds within the end zone without being touched , or is caught by the receiving team in the end zone but not advanced out of it , results in a touchback ; the ball is then placed at the receiving team ' s 20 - yard line , which becomes the line of scrimmage . A kickoff that goes out of bounds anywhere other than the end zone before being touched by the receiving team is an illegal kick : the receiving team has the option of having the ball re - kicked from five yards closer to the kicking team ' s goal line , or they may choose to take possession of the ball at the point where it went out of bounds or 30 yards from the point of the kick ( 25 yards in high school ) , whichever is more advantageous . Other free kicks . A free kick is also used to restart the game following a safety . The team that was trapped in its own end zone , therefore conceding two points to the other team , kicks the ball from its own 20 - yard line . This can be a place kick ( in the NFL , a tee cannot be used ) , drop kick or punt . In the NFL and high school , a free kick may be taken on the play immediately after a fair catch ; see " fair catch kick " below . Scoring . Field goal ( 3 points ) . A field goal is scored when the ball is place kicked , drop kicked , or free kicked after a fair catch or awarded fair catch ( High School or NFL only ) between the goal posts behind the opponent ' s end zone . The most common type of kick used is the place kick . For a place kick , the ball must first be snapped to a placeholder , who holds the ball upright on the ground with his fingertip so that it may be kicked . Three points are scored if the ball crosses between the two upright posts and above the crossbar and remains over . If a field goal is missed , the ball is returned to the original line of scrimmage ( in the NFL , to the spot of the kick ; in high school , to the 20 - yard line if the ball enters the end zone , or otherwise where the ball becomes dead after the kick ) or to the 20 - yard line if that is further from the goal line , and possession is given to the other team . If the ball does not go out of bounds , the other team may catch the kicked ball and attempt to advance it , but this is usually not advantageous . One official is positioned under each goalpost ; if either one rules the field goal no good , then the field goal is unsuccessful . A successful field goal is signaled by an official extending both arms vertically above the head . A team that successfully kicks a field goal kicks off to the opposing team on the next play . Touchdown ( 6 points ) . A touchdown is achieved when a player has legal possession of the ball and the ball crosses an imaginary vertical plane above the opposing team ' s goal line . After a touchdown , the scoring team attempts a try for 1 or 2 points ( see below ) . A successful touchdown is signaled by an official extending both arms vertically above the head . For statistical purposes , the player who advances the ball into or catches it in the end zone is credited with the touchdown . If a forward pass was thrown on the play , the quarterback is also credited with a passing touchdown . Try for extra point ( 1 or 2 points ) . A try is more frequently called an extra - point attempt or a PAT ( abbreviation of " Point After Touchdown " ) . Either one or two additional points may be scored during the try . The ball is spotted at the 2 yard line ( NFL ) or 3 yard line ( college / high school ) , and the team is given one untimed play to earn points : Safety ( 2 points ) . The uncommon safety is scored if a player causes the ball to become dead in his own end zone ; two points are awarded to the opposing ( usually defending ) team . This can happen if a player is either downed or goes out of bounds in the end zone while carrying the ball , or if he fumbles the ball , and it goes out of bounds in the end zone . A safety is also awarded to the defensive team if the offensive team commits a foul which is enforced in its own end zone . A safety is " not " awarded if a player intercepts a pass or receives a kick in his own end zone and is downed there . This situation , in which the opponent caused the ball to enter the end zone , is called a touchback ; no points are scored , and the team that gained possession of the ball is awarded possession at its own 20 yard line . If the interception or reception occurs outside the end zone , and the player is carried into the end zone by momentum , the ball is placed at the spot of the catch and no safety is awarded . A safety is signaled by a referee holding both palms together above the head , fingertips pointing upwards . After a safety , the team that conceded the safety kicks a free kick ( which may be a punt , place kick , or drop kick ) from its 20 yard line . Fair catch kick ( High school or NFL only , 3 points ) . A free kick ( see above ) may be taken on the play immediately after any fair catch of a punt . In the NFL , if the receiving team elects to attempt this and time expired during the punt , the half is extended with an untimed down . The ball must be held on the ground by a member of the kicking team or may be drop kicked ; a tee may not be used . ( High school kickers may use a tee ) . This is both a field goal attempt and a free kick ; if the ball is kicked between the goal posts , three points are scored for the kicking team . This is the only case where a free kick may score points . This method of scoring is extremely rare , last successfully completed in the NFL by Ray Wersching in 1976 . It is only advantageous when a team catches a very short punt with very little time left . Note that a team is unlikely to be punting with only a few seconds left in a half , and it is rarer still for punts to be caught near field goal range . The officials ' signal for a successful fair catch kick is the same as for a field goal . Officials . The game is officiated by a crew of three to seven officials . Every crew will consist of a " referee " , who is generally in charge of the game and watches action on the quarterback and in the offensive backfield ; an " umpire " , who handles spotting the ball and watches action on the offensive line ; and a " head linesman " , who supervises placement of the down box and line - to - gain chains . The crew may also consist of a " line judge " , " back judge " , " field judge " and " side judge " , in the order listed : i . e . a crew of five officials has a referee , umpire , head linesman , line judge and back judge . Officials are selected by the teams in advance or appointed by the governing league . Note that unlike some other sports , no football officials — not even at the NFL level — are full - time employees of the league ; they all officiate on a part - time basis . In the other three major North American professional sports leagues - - Major League Baseball , the NBA and NHL - - officials are employed by their respective leagues . The sheer volume of games in the other three sports necessitates full - time officials ; the NFL regular season is only 16 games long , compared to 162 games for MLB and 82 for the NBA and NHL . During the game , the officials are assisted in the administration of the game by other persons , including : a " clock operator " to start and stop the game clock ( and possibly also the play clock ) ; a chain crew who hold the " down indicator " and the " line - to - gain chains " on the sideline ; and " ball boys " , who provide footballs to officials between downs ( e . g . a dry ball each down on a wet day ) . These individuals may be provided by the teams involved — it is common for a high school coach ' s son or daughter to act as ball boy for the team . Fouls and their penalties . Because football is a high - contact sport requiring a balance between offense and defense , many rules exist that regulate equality , safety , contact , and actions of players on each team . It is very difficult to always avoid violating these rules without giving up too much of an advantage . Thus , an elaborate system of fouls and penalties has been developed to " let the punishment fit the crime " and maintain a balance between following the rules and keeping a good flow of the game . Players are constantly looking for ways to find an advantage that stretches the limitations imposed by the rules . Also , the frequency and severity of fouls can make a large difference in the outcome of a game , so coaches are constantly looking for ways to minimize the number and severity of infractions committed by their players . It is a common misconception that the term " penalty " is used to refer both to an infraction and the penal consequence of that infraction . A " foul " is a rule infraction for which a penalty is prescribed . Some of the more common fouls are listed below . In most cases when a foul occurs , the offending team will be assessed a penalty of 5 , 10 or 15 yards , depending on the foul . Also , in most cases , if the foul is committed while the ball is in play , the down will be replayed from the new position ( for example , if the offense commits a foul on a first - down play , the next play will still be first down , but the offense may have to go 15 yards , or farther , to achieve another first down . ) But if a defensive foul results in the ball advancing beyond the offense ' s first - down objective , the next play will be the first down of a new series . Some penalties ( typically for more serious fouls ) , however , require a loss of down for the offense ; and some defensive fouls may result in an automatic first down regardless of the ball position . In all cases ( except for ejection of a player or , in rare cases , forfeiture of the game ) , the non - offending team is given the option of declining the penalty and letting the result of the play stand ( although the Referee may exercise this option on their behalf when it is obvious ) , if they believe it to be more to their advantage . For some fouls by the defense , the penalty is applied in addition to the yardage gained on the play . Most personal fouls , which involve danger to another player , carry 15 - yard penalties ; in rare cases , they result in offending players being ejected from the game . In the NFL , if a defensive foul occurs after time has expired at the end of a half , the half will be continued for a single , untimed play from scrimmage . Under college rules , any accepted penalty when time has expired at the end of any quarter results in an extension for one untimed down . In the NFL , with three exceptions , no penalty may move the ball more than half the distance toward the penalized team ' s goal line . These exceptions are defensive pass interference ( see the discussion of that foul for more details ) , intentional grounding , and offensive holding – but in this last case the exception pertains only if the infraction occurs within the offensive team ' s own end zone , in which case an automatic safety is assessed ( intentional grounding from the end zone also carries an automatic safety ) . Under college rules , the same half - the - distance principle applies , but any offensive fouls involving contact in their end zone ( e . g . holding , illegal blocking or personal fouls ) result in a safety . Timeouts . Each team receives three timeouts per half ( if the game goes to overtime , each team receives additional timeouts ) , making for a total of six timeouts per team in a regulation game . Timeouts received in the first half may not be used in the second half or overtime . In professional football , a team must have at least one remaining timeout to challenge an official ' s call . Instant replay . In the NFL , a number of rulings can be reviewed by officials or challenged by coaches ( see Instant replay ) . If a coach wants to challenge a play , he must do so before the next play begins , and he does so by throwing a red flag similar to the officials ' yellow flags . Coaches are allowed two challenges per game and are granted a third if their first two are successful . The team loses a timeout if they lose the challenge . Therefore , they cannot challenge if they do not have timeouts . Plays within the two - minute - warning and overtime cannot be challenged ; any review must be initiated by a replay official off - field . The referee performs the actual review via a video screen on the sideline . The referee will announce the result of instant replay reviews over his wireless microphone . Beginning in the 2011 NFL Season , an instant replay review by the booth official will now be automatic for every play ruled by the referees on the field to have scored points . This is seen as another step in the " modernization " of sports . Every scoring play will be reviewed now , which saves coaches from using up their challenges on close plays in the endzone . And since the 2012 season , the booth official also reviews all turnovers during the game . In college , coaches are allowed one challenge per game by first requesting a timeout . Otherwise , a replay official in the press box observes all plays . If he deems a ruling may be in error , he notifies the officials on the field to interrupt the game before the beginning of the next play . The replay official performs the review and relays the decision to the referee , who announces the result . Not every conference employs replay , which is optional . High school rules do not provide for video review of any decisions by officials during the game . Further , the use of television or video tape for coaching purposes during the game is prohibited . If a coach feels a rule has been misinterpreted , he may call timeout and request a coach - referee conference to " discuss " the ruling with the referee , but no replay equipment will be consulted during the conference .