League of Legends is a game of precision, timing, and layered mechanics—and among the most confusing for players, both new and experienced, is the concept of “slows.” With dozens of champions, items, and abilities capable of reducing enemy movement speed, one question consistently emerges: Do slows stack?
The answer is both yes and no—and it all comes down to how Riot Games handles one of the game’s most subtle yet powerful forms of crowd control.
What Is a “Slow” in League of Legends?
A slow is a debuff that reduces a champion’s movement speed, making it easier to catch or kill them—or harder for them to escape or chase. Slows can come from abilities (like Nasus’ Wither), items (such as Rylai’s Crystal Scepter), or summoner spells (notably, Exhaust).
But what happens when multiple slows hit the same target? Is the effect amplified—or do they cancel each other out?
The Mechanics: How Simultaneous Slows Interact
When a champion is affected by multiple movement speed slows simultaneously from different sources, the strongest slow is applied at its full effectiveness. Any additional simultaneous slows from different sources then apply a reduced percentage (historically 35%) of their slowing power on the target’s remaining movement speed, stacking multiplicatively.
For example, if a champion with 400 movement speed is hit by a 50% slow and a 30% slow at the same time:
- The strongest slow (50%) is applied: 400 * (1 – 0.50) = 200 movement speed remaining.
- The additional slow (30%) applies at 35% effectiveness (0.30 * 0.35 = 0.105 or 10.5%): 200 * (1 – 0.105) = 179 movement speed. The champion’s speed would be reduced to 179, not 400 * (1 – 0.50 – 0.30) = 80 (additive stacking).
This system prevents players from being immobilized by multiple overlapping slows.
Exceptions and Nuances
While the general rule is that the strongest simultaneous slow takes priority and others stack multiplicatively with reduced effectiveness from different sources, there are nuances:
- Same Sources: Slows from the same named item or ability effect usually do not stack; only the strongest one is applied.
- Refreshing: Some slows may simply refresh the duration of an existing slow rather than applying a new stack or modifying the existing one’s intensity.
- Unique Interactions: Specific abilities or items may have unique coding that alters how they interact with other slow effects.
- Updates: Riot occasionally adjusts the exact percentages or rules for slow stacking, so specific interactions can change with patches.
The Strategic Impact of Slows
While slows don’t stack additively, applying multiple slows still matters. Continually refreshing a slow or applying a new, stronger one can help keep enemies locked down.
This is especially true in coordinated plays where champions like Ashe, Lulu, and Nunu layer slows in succession to control objectives or kite opponents.
Common Myths About Slows
- Myth: All slows stack additively. Reality: They stack with the strongest taking priority, and subsequent simultaneous slows from different sources applying at reduced multiplicative effectiveness.
- Myth: Red buff and item slows always stack together fully. Reality: Only the strongest slow takes effect in many cases, and other simultaneous slows from different sources stack with reduced effectiveness.
- Myth: Slows from multiple allies stack additively. Reality: Usually false. However, chain slowing—where different slows are applied in sequence—remains a viable tactic.
Final Thoughts
Slows in League of Legends don’t stack in the way many assume—but understanding how they interact can dramatically improve your gameplay. Whether you’re setting up a gank or peeling for your carry, knowing how to layer slows effectively can turn a skirmish in your favor.
In a game where movement often means survival, slowing your enemies the smart way is still one of the fastest routes to victory.
Written by:
Christian