IHM Knowledge Center
What Is Coincidental Penalties in Ice Hockey?
What happens when players from both teams receive penalties at the same time, and why does the game often stay at even strength?
Editor: Coach Mark • Updated: April 19, 2026
Short Answer
Coincidental penalties occur when players from both teams are penalized at the same time with equal penalties, resulting in no manpower advantage.
Full Explanation
Coincidental penalties happen when both teams commit infractions at the same time, and each team receives the same type and duration of penalty.
Because the penalties cancel each other out, both teams remain at equal strength on the ice.
The penalized players serve their time, but they do not create a power play situation.
This often occurs during scrums, fights, or simultaneous infractions.
NHL vs IIHF Rule Differences
Both NHL and IIHF apply coincidental penalties in similar ways.
In the NHL, players serving coincidental penalties may return during play without a stoppage.
In IIHF, procedures may differ slightly regarding player return timing.
The principle of equal penalties canceling each other remains consistent.
How Coincidental Penalties Affect the Game
Since both teams lose the same number of players, the on-ice strength remains balanced.
For example:
- 5-on-5 becomes 4-on-4
- 4-on-4 becomes 3-on-3
This can create more open ice and increase scoring chances.
The game flow often becomes faster and more dynamic.
Why These Situations Are Controversial
Coincidental penalties are controversial because fans may expect one team to gain an advantage.
Instead, both teams are penalized equally.
Controversy usually arises from:
- Perceived unequal severity of infractions
- Scrum situations involving multiple players
- Referee judgment calls
- Timing of penalties
These calls depend on interpretation.
Edge Case: Unequal Coincidental Penalties
A key edge case occurs when penalties are called at the same time but are not equal.
For example, one player receives a minor penalty while the other receives a major.
In this case, the penalties do not fully cancel out, and a power play may result.
This creates complex situations in game flow.
IHM Signal System: How to Read the Situation
To understand coincidental penalties, focus on these signals:
- Timing signal: Were penalties called simultaneously?
- Type signal: Are the penalties equal in duration?
- Balance signal: Does either team gain advantage?
Trigger-level rule:
If both teams receive equal penalties at the same time, they almost always cancel out and no power play is created.
If penalties differ in severity or timing, an advantage may still occur.
IHM Insight: Why This Rule Is Misunderstood
Coincidental penalties are misunderstood because fans focus on the number of penalties rather than their equality.
Two penalties do not automatically cancel each other unless they are equal.
Different combinations can lead to different outcomes.
Understanding equality vs quantity is key.
Mini Q&A
What are coincidental penalties?
Penalties given to both teams at the same time.
Do they cancel out?
Yes, if equal.
Does it create a power play?
No.
What happens on the ice?
Teams play with fewer players equally.
Why are they used?
To penalize both teams fairly.
Why This Rule Exists
Coincidental penalties exist to maintain fairness when both teams commit infractions simultaneously.
They prevent one team from gaining an unfair advantage.
Key Takeaways
- Coincidental penalties cancel each other
- No power play is created
- Teams remain at equal strength
- Common in scrums
- Equality determines outcome