When does the clock stop—and when does 10 seconds come off?

Scope: NFL first, NCAA compared separately

This page applies the 2026 Official Playing Rules of the National Football League, which the NFL states are in effect for its 2026 season. “NFL” below means preseason, regular-season and postseason play under that rulebook unless a competition provision says otherwise.

The college comparison uses the NCAA's official 2025 Football Rules Book together with the 2026 NCAA Football Rules Changes, approved in March and April 2026 and effective for the 2026 season. As of 12 August 2026, the NCAA rules page still labels the base PDF “2025” and publishes the 2026 changes separately. NFHS high school, Canadian, youth and flag football use different timing codes and are not covered by the rulings on this page.

Stopping and restarting are two decisions

NFL Rule 4-4 tells the clock operator when to stop: among other events, when the ball is out of bounds, a forward pass is incomplete, a foul occurs, a down ends with a change of possession, the ball is dead on or behind a goal line, the two-minute warning is reached, or an official signals another timeout.

Rule 4-3 then decides the restart. The default after a timeout is the next snap, but the rule supplies important exceptions that start time on the referee's ready-for-play signal. A television graphic showing “clock stopped” therefore does not by itself tell the offense how long time will remain stopped.

What happens after familiar plays

• Runner tackled inbounds: the clock continues unless a foul, injury, measurement, review, timeout or other rule creates a stoppage.
• Incomplete forward pass: the clock stops and normally starts on the next snap.
• Charged team timeout: the clock starts on the next snap. Each team has three charged timeouts per half under Rule 4-5-1.
• Change of possession: the clock stops at the end of the down and starts on the next snap.
• Runner out of bounds: apply the special windows below; the answer is not “always on the snap.”
• Foul: after administration, Rule 4-3-2 generally restores the clock status that would have applied without the foul, subject to its late-period exceptions and any specific runoff rule.
• Referee's timeout: a measurement or administrative delay does not automatically buy a snap restart; ordinarily the clock resumes as though that timeout had not occurred.

The NFL uses two different late-game windows

Under NFL Rule 4-3-2(a), a runner who goes out of bounds on a scrimmage play stops the clock. It restarts when the referee signals that the ball has been returned to play, except after a change of possession, after the two-minute warning of the first half, or inside the final five minutes of the second half. In those exceptions it waits for the snap.

A loose ball creates an important boundary case. Rule 4-3-2(f) says that when a fumble or backward pass goes out of bounds, the clock starts on the referee's signal after the ball is returned to the field. That is not the same restart rule as a runner stepping out late. A backward pass deliberately thrown out after the two-minute warning can also be a time-conserving foul under Rules 4-7-1 and 8-7-2.

An NFL first down is not a routine clock stop

The NFL does not stop the game clock merely because the offense gains a first down. If a runner is tackled inbounds beyond the line to gain, time normally continues while the ball is spotted. Officials may take a referee's timeout for a possible measurement, but Rule 4-3-2(d) restores the clock as though that administrative timeout had not occurred.

This is commonly confused with older college practice. Under the current NCAA baseline, an inbounds Team A first down does not stop the clock outside the final two minutes of the second and fourth quarters. After the NCAA Two-Minute Timeout, it stops while the first down is awarded and restarts on the referee's signal—not on the snap.

A flag does not automatically freeze time

NFL Rule 4-3-2(e) generally starts the clock after penalty administration as though the foul had not occurred. It instead starts on the snap when the foul occurs after the first-half two-minute warning, inside the final five minutes of the second half, or in another listed exception. That five-minute fourth-quarter restart window is broader than the usual two-minute runoff window.

Penalty yards, clock restart and runoff are separate rulings. Officials can enforce yardage without a runoff; the offended team may sometimes accept the yardage but decline the runoff; and declining the penalty can also remove the runoff. The options depend on the specific rule, not a general right to choose any clock result.

The NFL Rule 4-7 decision path

1. Was the play after the two-minute warning? Rule 4-7's illegal time-conservation remedy applies after the warning in either half.
2. Was the game clock running? An offensive act must stop or prevent the proper running of time; a foul while the clock was already stopped does not create this runoff.
3. Was it a listed or equivalent illegal act? Rule 4-7-1 includes a dead-ball foul that stops time, intentional grounding, an illegal forward pass, a backward pass thrown out of bounds, throwing or spiking the ball after the down except after a touchdown, and illegally batting or kicking the ball out of bounds.
4. Is the yardage penalty accepted? The defense may accept the yardage and decline the runoff. If it declines the yardage penalty, the runoff is also declined.
5. Will the offense use a timeout? A remaining charged timeout can replace the runoff; the next game-clock start is then on the snap.
6. If enforced: officials remove 10 seconds, set the play clock to 30 seconds and start both clocks on the ready-for-play signal. The runoff can end the half.

A spike is a down, not a free timeout

NFL Rule 8-2-1, Item 3 allows a T-formation quarterback to stop a running clock if, immediately after receiving the snap, the quarterback begins a continuous throwing motion and throws the ball directly into the ground. The snap makes the ball live, time elapses, and the spike consumes a down before the incomplete pass stops the clock.

A delayed spike is intentional grounding under Item 4. After the two-minute warning, that foul can also trigger Rule 4-7's 10-second runoff when the clock was running. A team cannot plan on “spiking after the runoff” if the enforced runoff ends the half.

NFL injury runoffs are tied to excess timeouts

Safety comes first: an official calls an injury timeout when a player is judged injured or attendants enter. Under NFL Rules 4-5-3 and 4-5-4, the player normally misses the completion of one down, with exceptions including an opponent's foul and certain team-timeout or period-ending situations.

After the two-minute warning, Rule 4-5-4 ordinarily charges the injured player's team a remaining timeout. If that team has none, it receives an excess team timeout. A 10-second runoff is available only when the excess timeout is charged to the team in possession and it stops the clock or delays a ready-for-play start; the defense chooses whether to apply it. The NFL expressly says there is never a 10-second injury runoff against the defensive team.

No injury runoff is enforced when both teams have an injured player in the same sequence. A foul during the down also prevents an injury runoff because the foul itself stopped the clock. Injuries caused by an opponent's foul and injuries during a change of possession, touchdown, safety, successful field goal, free kick or attempted try have separate timeout exceptions in Rule 4-5-4.

A changed ruling can restore time and remove ten seconds

NFL Rule 15-5 resets the game clock to when the ball should have been declared dead if replay changes the ruling. For a play beginning after the two-minute warning, if the corrected result produces a running clock—or one that would have restarted before the next snap—the clock runs for 10 seconds from that reset time, the play clock is set to 30, and both start on the ready-for-play signal.

Neither team may decline this replay runoff, but either team may use a remaining charged timeout to prevent it. With a timeout, the game clock starts on the snap and the play clock is set to 25. If fewer than 10 seconds remain after the corrected dead-ball time, the NFL rule says the half or game is over.

The NFL does not give the defense a mirror-image runoff

For a defensive time-conserving act under Rule 4-7, the play clock is reset to 40 seconds and the game clock starts on the ready signal; the offense may choose a snap start. The defense can use a remaining timeout instead of having the game clock started.

Rule 4-7-3 adds a sharper remedy in the final 40 seconds of either half. If a defensive time-conserving foul or an excess timeout for a defensive injury occurs while time is running, the half ends unless the defense has a timeout, or the offense chooses a snap start or elects to continue after the ready-for-play start. This prevents the defense from manufacturing a stoppage to preserve a final possession.

Expiry and the legal end of a period differ

If the game clock reaches 0:00 while the ball is live, NFL Rule 4-8-1 lets the down finish. Rule 4-8-2 can then extend a period for an untimed down—for example, at the offense's option after an accepted defensive live-ball foul on the expiring play. An offensive foul normally does not extend the period, and an offensive score on the last play of a half is not counted when that rule applies.

A runoff is different: if its administration ends the half, there is no live down to finish and no opportunity to snap merely because the offense had intended to spike. Period-extension exceptions remain rule-specific, so “the clock hit zero” is only the beginning of the ruling.

A receiver steps out with 6:12 left

Situation: in the fourth quarter, a receiver catches the ball and runs out of bounds at 6:12 with no foul or change of possession.

Ruling: the clock stops, then starts on the referee's signal when the ball is returned to play. The decisive fact is that 6:12 is outside the final-five-minute exception in NFL Rule 4-3-2(a). At 4:58 in the same situation, it would wait for the snap.

Intentional grounding with 0:08 left

Situation: after the second-half two-minute warning, the offense has no timeouts. With the clock running at 0:08, the quarterback intentionally grounds a pass to stop time. The defense accepts the penalty and runoff.

Ruling: enforce the intentional-grounding penalty and the Rule 4-7 runoff; the half ends. The decisive facts are that the clock was running, the act occurred after the warning, grounding is listed, and no timeout is available to avoid the runoff.

Replay changes incomplete to down inbounds

Situation: a play begins with 0:18 left after the two-minute warning. It is ruled incomplete at 0:14, but replay changes it to a catch with the runner down inbounds at 0:14. The offense has one timeout.

Ruling: reset the game clock to 0:14. Under NFL Rule 15-5-2, the corrected running-clock ruling creates a 10-second runoff unless either team uses a timeout. If the offense uses its timeout, 0:14 remains and the game clock starts on the snap; otherwise the ready-for-play administration applies.

Both teams have an injured player

Situation: after the two-minute warning, a running-clock play ends inbounds and players from both teams require injury timeouts. The offense has no charged timeouts.

Ruling: there is no 10-second injury runoff. NFL Rule 4-5-4, Note 5 bars yardage and runoff penalties when injury timeouts are called for both teams. The player's medical status is not judged by whether a clock remedy applies.

College timing is similar, not identical

• Late-half marker: NCAA timing provisions use the Two-Minute Timeout in the second and fourth quarters. The NFL uses its two-minute warning for runoffs, but uses a separate final-five-minute window for several second-half restarts.
• Out of bounds: under NCAA Rule 3-3-2, a Team A runner, fumble or backward pass out of bounds before the Two-Minute Timeout starts the clock on the referee's signal; after the timeout it normally starts on the snap. The NFL separately treats a fumble or backward pass out of bounds as a ready-for-play restart.
• Foul runoff: NCAA Rule 3-4-4 permits a 10-second subtraction, at the offended team's option, when either team commits an accepted foul after the Two-Minute Timeout, before a change of possession, while the clock is running, and that foul immediately stops it. The fouling team may use a remaining timeout to avoid the subtraction.
• Injury runoff: NCAA Rule 3-3-6-f gives the opponent a runoff option when a player's injury is the only reason for the late stoppage, subject to exceptions; unlike the NFL excess-timeout rule, this can apply to an injury on either team.
• Replay in 2026: in NCAA games that use optional instant replay, Rule 12-3-6 supplies the late replay runoff. When the late review is initiated by the replay official and the ruling is upheld, the 2026 amendment to Rule 3-2-4-c-12 preserves the existing play-clock time, resetting it to 10 seconds if less than 10 remained; an overturned ruling can require a different reset.

Five shortcuts that produce the wrong ruling

• “Out of bounds always means snap”: not in the NFL outside its late windows, and not for an NFL fumble or backward pass that goes out.
• “Every accepted penalty stops the clock until the snap”: restart status depends on Rule 4-3 and the period; runoff is a separate question.
• “Any late injury costs 10 seconds”: NFL injury runoffs depend on an offensive excess timeout and specific clock conditions; listed exceptions can remove them.
• “The defense gets the same runoff as the offense”: NFL Rule 4-7 uses different remedies for defensive clock conservation, including the final-40-second rule.
• “NFL and college first-down timing match”: neither now has a routine all-game stop, but NCAA still stops an inbounds offensive first down after its Two-Minute Timeout and restarts on the referee's signal.

NFL 2026 and NCAA 2026-season sources

• NFL — 2026 Official Playing Rules — Rules 4-3 to 4-8 on starts, stops, timeouts, time-conserving acts and period extensions; Rule 8-2-1 on grounding and spikes; Rule 15-5 on replay clock administration.
• NFL — 2026 Official Playing Rules PDF — controlling 2026-season edition; game timing at rulebook pages 11–15 and replay clock administration at page 63.
• NCAA — Football Playing Rules — official index for the current base rulebook, casebook and 2026 amendments.
• NCAA — 2025 Football Rules Book — Rule 3-3 on clock starts and injury timeouts, Rule 3-4 on 10-second subtractions, and Rule 12 on instant replay; used as the base text for the 2026-season comparison.
• NCAA — 2026 Football Rules Changes — approved March/April 2026 and effective with the 2026 season, including Rule 3-2-4-c-12 replay play-clock administration.
• NCAA — 2026 Instant Replay Case Book — May 2026 edition; Rule 12 clock adjustment, late-half runoff and time-restoration procedures.

Source note: checked against the official NFL and NCAA materials above on 12 August 2026. The NFL rulebook controls the main rulings. The NCAA comparison combines the NCAA site's 2025-labelled base book with its separate 2026 effective amendments. Conference game-management policies may supplement NCAA replay operations; other football codes require their own current books.