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Complete Guide To Referee Signals In American Football

Football may seem complicated with all of the complex rules. Yellow flags are consistently thrown throughout the game, which may overwhelm the average football viewer.

We’ve created a referee signal guide that can help you better understand why referees throw the yellow flags and how your team can avoid penalties.

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Penalties In Football

Before we start breaking down the penalties in football, it’s essential to learn why referees throw a yellow flag.

The yellow flag in football, which is a cloth that typically has rocks or counterweight at the other end, is thrown by referees when they identify a penalty.

Flag in football

There are 3 phases when the referee may throw a flag.

  • Pre-Snap
  • During The Play
  • After The Play

To understand why the referee throws a flag, you must understand the 3 phases of a football play. Let’s learn more about these three phases.

Pre-Snap Penalty

A pre-snap penalty is any illegal action or movement before the ball is snapped from the center to the quarterback.

These penalties are often movement penalties, as only one offensive player may be moving in motion once the offense is set. Defensively, pre-snap penalties often occur when a defensive player crosses the line of scrimmage before the ball is snapped.

To avoid pre-snap penalties on offense, it’s important to learn the cadence of the offense and move when the ball is snapped. On defense, it’s important to watch the football and make sure it’s snapped to the quarterback before coming across the line of scrimmage.

During The Play Penalty

After the ball is snapped, there are multiple rules that are now into play.

Each referee has a location on the field for which they are responsible. If any penalties occur during the play, it’s their job to throw the flag.

For example, the line judge is responsible for any pre-snap penalty on the line of scrimmage. If a penalty is identified, they will blow the whistle and stop the ball from being snapped.

To learn more about each referee on the field and their duties, we recommend you read here.

After The Play Penalty

After the ball carrier is tackled and the play is officially over, there are still penalties that can occur.

These penalties are often related to unnecessary roughness.

Referees will throw a flag and mark it as a “dead ball” penalty. Dead ball means that the play is over, and the ball is dead. These penalties will often result in a 15-yard penalty for the guilty team.

Now that you understand the 3 phases of throwing a flag let’s learn why referees throw flags throughout the football game.

Pre-Snap Offensive Penalties

The first type of penalty is the pre-snap penalty. These penalties will happen before the center snaps the ball.

When a referee identifies a pre-snap penalty, they will blow the whistle, throw the flag and immediately stop the ball from being snapped.

Delay Of Game

Delay of game in football

Reason: It occurs when the offense doesn’t snap the football before the play clock expires.

Result: 5 Yard Penalty

False Start

false start in football

Reason: Called when an offensive player moves after establishing their set position.

Result: 5 Yard Penalty

Illegal Shift

illegal shift in football

Reason: Called when two players go in motion simultaneously after establishing their set position.

Result: 5 Yard Penalty

Illegal Substitution

illegal substitution in football

Reason: Having 12 players on the field or illegally breaking the huddle with 12 players.

Penalty: 5 Yard Penalty

Pre-Snap Defensive Penalties

Encroachment

encroachment in in football

Reason: Called when a player jumps offsides and touches another player.

Result: 5 Yard Penalty

Neutral Zone Infraction

neutral zone infraction in football

Reason: Called when another player passes the neutral zone.

Result: 5 Yard Penalty

Offsides

offsides in football

Reason: Called when a player lines up with a part of their body past the line of scrimmage. Learn the difference between offsides, neutral zone infractions, and encroachment in this article here.

Result: 5 Yard Penalty

Post-Snap Offensive Penalties

Post-snap penalties can be called as soon as the ball is snapped from the center to the quarterback. Referees each have a certain area of the field they are watching.

If any penalty occurs, they will throw a flag in the vicinity of where the foul occurred.

Here are the post-snap penalties that are called in football.

Illegal Block In The Back

illegal block in the back in football

Reason: Blocking a player in the back to gain an advantage while running a play.

Result: 10 Yard Penalty

Chop Block

chop block in football

Reason: Blocking a player from the waist up, then a second player blocking from the waist down.

Result: 15 Yard Penalty

Clipping

clipping in football

Reason: Blocking a player from behind and below the waist, causing the player to fall.

Result: 15 Yard Penalty

Illegal Block Below The Waist

illegal block below the waist in football

Reason: Illegally blocking a player below the waist in certain areas of the field.

Result: 15 Yard Penalty

Illegal Forward Pass

illegal forward pass in football

Reason: Throwing a forward pass, passed the line of scrimmage.

Result: 5 Yard Penalty & Loss Of Down

Illegal Hands To The Face

illegal hands to the face in football

Reason: When a player illegally puts their hands on the face mask without grabbing the face mask ultimately.

Result: 10 Yard Penalty & Automatic First Down

Ineligible Receiver

ineligible receiver in football

Reason: If a receiver steps out of bounds, they are ineligible to be the first receiver to touch the football in bounds.

Result: 5 Yard Penalty

Intentional Grounding

intentional grounding in football

Reason: Called when the forward pass doesn’t reach the line of scrimmage or when a player isn’t in the area to catch the football.

Result: 10 Yard Penalty & Loss Of Down

Offensive Holding

offensive holding in football

Reason: Called when a player holds the jersey, shoulder pads, or body parts of a defensive player, restricting their movement.

Result: 10 Yard Penalty

Offensive Pass Interference

offensive pass interference in football

Reason: When an offensive player makes contact unfairly with a defensive player to play on a forward pass.

Result: 10 Yard Penalty

Tripping (Offense)

Tripping in football

Reason: When an offensive player deliberately sticks their legs out and trips a defensive player to gain an advantage.

Result: 10 Yard Penalty & Automatic First Down

Post-Snap Defensive Penalties

Facemask

Facemask in football

Reason: Called when a player grasps another player’s face mask in any way.

Result: 15 Yard Penalty

Horse Collar

Horse Collar in football

Reason: Called when a player tackles an offensive player by the back of their shoulder pads.

Result: 15 Yard Penalty

Defensive Pass Interference

Defensive pass interference in football

Reason: Called when a player unfairly makes contact with an offensive player to catch the football.

Result: 5 Yard Penalty (High School), Spot Foul Under 15 Yards (College), Spot Foul Anywhere On The field (NFL)

Roughing The Passer

roughing the passer in football

Reason: Called when the quarterback is hit after the ball is thrown.

Result: 15 Yard Penalty

Roughing The Kicker

roughing the kicker in football

Reason: Called when the kicker’s leg or plant leg is hit after the ball is kicked.

Result: 15 Yard Penalty

Running Into The Kicker

Running into the kicker in football

Reason: Called when the kicker is hit after the ball is kicked.

Result: 5 Yard Penalty

Targeting

Targeting in football

Reason: Called when a player goes helmet to helmet with another player in a violent manner.

Result: 15 Yard Penalty

Tripping (Defense)

Tripping in football

Reason: Called when a defensive player trips an offensive player to gain an advantage

Result: 10 Yard Penalty

Unsportsmanlike Conduct

Unsportsmanlike Conduct in football

Reason: Called when a player does something unsportsmanlike to football.

Result: 15 Yard Penalty

Other Penalties & Signals

Ball Ready

Ball ready in football

The referee signal for the ball is in play and ready for the offense to snap it.

Dead Ball

dead ball in football

Signaled when a dead ball, also known as a penalty, occurs after the play.

Ejection

Ejection in football

Called when a player or a coach is ejected from the game.

End Game

end of the game in football

This referee signals the game is over. The referee will take off his hat or raise the ball in the air.

First Down

First Down In Football

This referee signal indicates that the offense has gained enough yards for a first down.

Incomplete Pass

Incomplete Pass in football

This referee signal indicates the offense did not complete a forward pass.

Injury Timeout

Injury Timeout in football

Signaled when the referee needs to stop the clock for an injury or a coach’s timeout.

No Good

no good in football

Called by the referee standing under the field goal post, this signal indicates no good kick.

Personal Foul

Personal Foul in football

It is called when a player commits a penalty to hurt another player purposely.

Reset The Play Clock

reset the play clock in football

Signaled to the game clock operator, this tells them to reset the play clock.

Safety

safety in football

Signaled when the defense forces offense to either down the ball or fumble out of their end zone. Learn More about the safety in football here.

Sideline Warning

Sideline warning in football

Signaled when a referee warns the sideline or coach about their conduct.

Stop The Clock

stop the clock in football

It is signaled by the referee when he wants the game clock operator to stop the clock.

Touchback

touchback in football

It is signaled by the referee that a touchback has occurred from the kicking team.

Touchdown

touchdown in football

Signaled when a player crossed the goal line successfully for 6 points.

Ball Is Not Catchable

ball is not catchable in football

Signaled when the ball that is thrown is uncatchable after a defensive player makes contact

Waiving Off The Flag

waiving off the flag in football

Signaled when the referee makes a mistake and needs to waive off the flag.

Wind The Clock

wind the clock in football

Signaled to the game clock operator to start the clock.

Keep Learning

Below are articles to help you learn more about the rules of football.

Rules Of American Football – Beginner’s Guide

Difference Between Legal & Illegal Blocks In Football

Illegal Contact With Wide Receivers Explained

What Is A Flag In Football? Penalty Flags Explained

Can A Football Game End On A Penalty?

Football Overtime Rules: NFL Vs. College/High School

Understanding the 5 Yard Contact Rule In The NFL

Learn Offsides, Neutral Zone Infraction, and Encroachment

What Is A Safety In Football? Explained

Penalties in football are subjective to each referee. Referees will throw the flag if they believe they witnessed an offensive or defensive player commit a penalty.

Referees may miss a call from time to time due to poor positioning or not seeing a player committing a penalty. With 22 players on the field, it’s common for referees to miss 1-2 calls a game.