NBA Players, Substitutes and Coaches Rules

NBA Rule No. 3 establishes the regulations governing players, substitutes, coaches and team personnel during a professional basketball game. These rules determine how many players must be on the court, when substitutions are permitted, how starting lineups are submitted and what responsibilities belong to coaches and team captains.

The regulations also address unusual situations involving injuries, ejections and players who have committed six personal fouls. In addition, they establish requirements for player uniforms and restrict the conduct of coaches and other team personnel.

Although some of these rules have existed for decades, others have been revised to reflect changes in NBA game administration, player safety and league operations.

A. Five Players on the Court

Each NBA team must have five players on the court during normal play. Under NBA Rule No. 3, a team may not be reduced to fewer than five players.

A player is ordinarily disqualified from the game upon receiving a sixth personal foul. However, the NBA provides a special exception when a team has no remaining eligible substitutes.

If a player commits a sixth personal foul and all substitutes have already been disqualified, that player must remain in the game. The player is charged with the personal foul, the team is charged with a team foul, and the team is also assessed a technical foul.

Every additional personal foul committed by a player who remains in the game with six or more fouls is treated the same way, including offensive fouls.

All players who have six or more personal fouls and are required to remain in the game are subject to these provisions.

B. Injuries and Ejections When Only Five Players Remain

If a team has only five eligible players remaining and one becomes injured or is ejected, the player must be replaced by the most recently disqualified player who fouled out.

If another replacement becomes necessary, previously disqualified players return in reverse order of their disqualification.

Each re-entry by a player who was previously disqualified for six personal fouls results in a technical foul against that player's team.

C. Player Leaving the Court During Live Play

If a player leaves the playing court while the basketball is live, play continues until the next stoppage.

If the player is not ready to return, the team must replace that player.

No automatic technical foul is assessed for leaving the court under this provision, but the NBA League Office may review the incident and impose a fine or suspension.

Exceptions may apply under the NBA's rules governing specific violations.

At least 30 minutes before the scheduled beginning of the game, the official scorers must receive the name and uniform number of each player who will start.

Failure to provide the required starting-lineup information must be reported to the NBA League Office.

This requirement helps officials, scorers and game administrators verify player eligibility and prepare the official game records before the opening tip.

The previous version of this page listed a 10-minute deadline. That information has been updated to reflect the current NBA rule.

A. Captain and Co-Captain

An NBA team may designate a captain and a co-captain, for a maximum of two designated captains.

The captain may be any player on the active list who is in uniform, except a player-coach.

B. Communication With Officials

The designated captain is the only player permitted to ask an official about a rule interpretation during a timeout charged to the captain's team.

The captain may discuss the interpretation of a rule but may not dispute a judgment decision made by an official.

C. Captain Remaining on the Bench

A designated captain who remains on the bench continues to hold that designation throughout the game.

The captain does not have to be one of the five players currently on the court.

D. Replacing an Absent Captain

If the designated captain is absent from both the court and the bench, the head coach must immediately designate a new captain.

A. Coaching Area and Movement

The head coach may remain seated or stand within the permitted coaching area, extending from the substitution-box line nearest the team's bench to the baseline.

A coach may not cross the midcourt line. Doing so results in an immediate unsportsmanlike technical foul.

Assistant coaches and trainers must remain on the bench, subject to specific exceptions established by NBA rules.

Coaches and trainers may approach the scorer's table only during a dead-ball situation.

B. Player-Coaches

A player-coach, if permitted under NBA regulations, receives no special privileges.

While participating as a player, the individual must follow the same rules and restrictions that apply to every other player.

C. Conduct of Team Personnel

Club personnel who are not seated on the bench must conduct themselves in a manner that reflects favorably on the dignity of the game and the officials.

Violations may require a written report to the NBA League Office for possible disciplinary action.

D. Authorized Bench Personnel

Under Rule No. 3, the team bench may be occupied by a league-approved head coach, a maximum of three assistant coaches, players and a trainer.

During an altercation, the head coach and assistant coaches are permitted to enter the court as peacemakers.

This exception does not grant coaches permission to participate in a confrontation.

E. Suspended and Ejected Personnel

A player, head coach or assistant coach who is suspended from a game may not appear in the arena or stands where the team is playing before, during or after the game.

A player, coach or assistant coach who is ejected may remain only in the team's dressing room for the remainder of the game or leave the building.

Violation of these restrictions results in an automatic $2,000 fine.

The older version of this page listed a $500 fine. That amount has been updated to reflect the current NBA rule.

A. Reporting to the Scorer's Table

A substitute must report to the official scorer and position himself in the vicinity of the eight-foot substitution box in front of the scorer's table.

For purposes of this rule, the permitted vicinity extends from the 28-foot hash mark closest to the player's bench to the midcourt line.

The substitute must inform the scorer which player he will replace.

The scorer sounds the horn to indicate that a substitution has been requested. The horn is not required for substitutions occurring between periods or during timeouts.

B. Entering the Court

A substitute must remain in the permitted substitution area until an official beckons him onto the court.

If the basketball is about to become live, the official must withhold the signal allowing the substitute to enter.

A player must not enter the game without the official's authorization.

C. Readiness to Enter

A substitute must be ready to participate when called onto the court.

Officials are not required to delay the game while a player removes warm-up clothing or otherwise prepares to enter.

D. Replacing a Free Throw Shooter or Jumper

A substitute generally may not replace the player who is required to attempt a free throw or participate in a jump ball.

Exceptions apply when replacement is necessary because of injury, ejection or another situation specifically addressed by the rules.

Additional procedures appear in NBA Rule No. 6 and Rule No. 9.

The ordinary restriction on replacing a designated shooter should not be confused with the separate provisions governing technical-foul free throws.

E. When a Substitute Becomes a Player

A substitute becomes a player when an official beckons him onto the court or otherwise recognizes him as participating in the game.

After entering, the player ordinarily cannot be removed until the basketball has been legally touched by a player on the court.

Exceptions apply when:

• A personal foul is called.
• A technical foul is called.
• Possession changes.
• A timeout is granted.
• The infection-control rule must be administered.

F. Recalling a Substitute

A substitute may be recalled from the scorer's table before an official beckons him onto the court.

Once the player has been recognized as entering the game, the applicable participation rules take effect.

G. Re-Entering During the Same Dead Ball

A player may be replaced and later re-enter as a substitute during the same dead-ball period, provided the substitution satisfies the applicable rules.

H. Substitutions Following Backcourt Violations

When a violation results in a backcourt throw-in, a substitute must already be in the permitted substitution area at the time of the violation.

If the substitute was not in position, he must wait until the next legal opportunity to enter.

Exception: During the final two minutes of any period or overtime, officials allow a reasonable amount of time for a substitution.

I. Substitutions During Free Throws

When free throws are awarded, substitutes generally may enter before the final attempt if the basketball will remain in play afterward.

If the basketball will not remain in play after the final attempt, substitutions are generally permitted following that attempt.

Exceptions apply when a substitution is required because of disqualification, injury, ejection or another unusual situation.

J. Substitutions After a Made Field Goal

A substitute may not enter the game simply because either team has made a field goal.

A substitution is permitted when the basketball becomes dead because of a personal foul, technical foul, timeout, infection-control procedure or violation.

K. Suspensions of Play

Substitutions are not normally permitted during an official's suspension of play for:

• A delay-of-game warning.
• Retrieving an errant basketball.
• An inadvertent whistle.
• An instant replay review.
• Another unusual circumstance requiring a temporary stoppage.

Exceptions: A substitution may be permitted when play is suspended because a player is bleeding. If a seriously injured player must be removed, the opponent is permitted one substitution.

L. Disqualified Players

A player who has been disqualified cannot ordinarily return to the game.

The exception occurs when a team would otherwise have fewer than five players, as described in Section I.

M. Notification of Substitution Infractions

Notification and administration of substitution violations are governed by the procedures in NBA Rule No. 2, Section VII.

A. Jersey Numbers

Every NBA player must wear a jersey displaying a number on both the front and back.

The numbers must contrast with the jersey color so that officials, scorers, spectators and television viewers can identify players.

B. Number and Letter Measurements

Under NBA Rule No. 3, the number on the front of a player's jersey must be at least three-quarters of an inch high.

The number on the back must be at least six inches high.

Each player's surname must appear on the back of the jersey in letters at least two and one-half inches high.

The NBA may approve exceptions to certain uniform measurements and surname requirements.

C. Home and Visiting Uniforms

The traditional rule calls for the home team to wear light-colored jerseys and the visiting team to wear dark-colored jerseys, unless otherwise approved.

For neutral-site games and doubleheaders, the second team listed on the official schedule is considered the home team for purposes of this provision.

Modern NBA uniform scheduling allows teams to wear a wider variety of approved jersey colors and designs. The traditional light-versus-dark language therefore should not be interpreted as a requirement that the home team always wear white.

Several provisions in the original NBAHoopsOnline archive reflected older NBA regulations. The most significant differences between that version and the current published rule are summarized below.

Rules governing players, coaches and substitutions have been part of professional basketball since the NBA's earliest seasons. While the basic requirement of five players per team has remained consistent, the league has repeatedly refined the procedures used to administer substitutions, enforce player eligibility and regulate the conduct of coaches.

The six-personal-foul limit is one of the NBA's defining regulations. Unlike some other basketball competitions, the NBA disqualifies a player after six personal fouls rather than five. The league also maintains an unusual exception requiring a team to continue with five players even when every available substitute has already been disqualified.

Substitution procedures became increasingly important as NBA teams developed deeper rotations and more specialized lineups. The use of the scorer's table, substitution box and official horn ensures that player changes can be recorded accurately without disrupting live play.

Coaching regulations have also evolved. Modern head coaches have designated areas from which they may direct their teams, while assistant coaches and other personnel face separate restrictions intended to maintain order around the benches and scorer's table.

Uniform rules have changed alongside the NBA's growth into a global sports league. Although the traditional distinction between light home jerseys and dark visiting jerseys remains part of the rulebook, modern teams use multiple league-approved uniforms, including alternate designs and special editions.

How many players must an NBA team have on the court?

An NBA team must have five players on the court. The league has special procedures to prevent a team from being reduced below five players when all substitutes have been disqualified.

How many personal fouls does it take to foul out of an NBA game?

A player is ordinarily disqualified after committing six personal fouls.

Can an NBA player continue playing after six fouls?

Yes, but only under the exceptional circumstances described in Rule No. 3 when the team has no remaining eligible substitutes. Additional personal and team fouls, along with team technical fouls, are assessed.

When must NBA starting lineups be submitted?

The starting lineup information must be provided to the official scorers at least 30 minutes before the scheduled start of the game.

How many captains can an NBA team have?

An NBA team may designate one captain and one co-captain, for a maximum of two.

Can an NBA coach cross half court?

No. A coach who crosses the midcourt line is immediately assessed an unsportsmanlike technical foul.

Can NBA teams substitute after a made basket?

Not solely because a field goal has been made. A substitution requires a qualifying dead-ball situation.

Can a player enter an NBA game without reporting to the scorer?

A substitute must follow the required reporting procedure and receive authorization from an official before entering.

Can a player who fouled out return to an NBA game?

Normally no. The exception occurs when a team must return a previously disqualified player to maintain five players on the court.

Does the NBA require home teams to wear white?

No. Although the traditional rule describes light-colored home uniforms and dark-colored visiting uniforms, the league approves modern uniform combinations that do not always follow that pattern.

NBA Official — Rule No. 3: Players, Substitutes and Coaches

NBA Official — Rule No. 2: Duties of the Officials

NBA Official — Rule No. 9: Free Throws and Penalties

NBA Official — Rule No. 12: Fouls and Penalties

Complete NBA Official Rulebook

This page summarizes NBA Rule No. 3 for educational and historical reference. Official NBA regulations govern all interpretations, exceptions and enforcement procedures.

NBA Rules and Regulations — Main NBA rules archive.

NBA Officials and Referees — Duties of referees, scorers and timers.

NBA Fouls and Penalties — Personal, technical and flagrant fouls.

NBA Free Throw Rules — Free throw procedures and penalties.

NBA Ball in Play Rules — Live-ball and dead-ball procedures.

NBA Shot Clock Rules — Possession timing and the 24-second clock.

NBA Violations and Penalties — Common basketball violations.

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