'Bottleneck In,' 'At,' or 'To': Which Preposition Is Correct?

Bottleneck trips up a lot of non-native speakers not on meaning, but on the small word right after it. Getting the preposition wrong is one of the most common tells that English isn't a writer's first language.

Use "in" for a process or workflow, "at" for a stage or point, and "to" for an outcome like growth or scaling. Never "bottleneck of."

Each preposition attaches to a different kind of thing

"'A bottleneck in the approval process' — locates it inside the workflow."

"In" places the bottleneck inside something bigger — a process, a workflow, a pipeline. The bottleneck is one part of that larger thing.

"'A bottleneck at the QA stage' — pins it to one specific point."

"At" is narrower. It pins the bottleneck to one identifiable stage, not the whole surrounding process.

"'The bottleneck to scaling is onboarding capacity' — connects it to the outcome."

"To" is different again — it connects the bottleneck to the outcome it's capping, usually growth, scaling, or some other forward-looking result.

The error to avoid

"Bottleneck of [process]" is the most common error and isn't a natural workplace pattern.

Common mistakes

Mistake: "the bottleneck of the process."

It's one of the most common non-native errors with this word — swap it for "in the process" every time. "Of" implies possession or composition, which isn't the relationship a bottleneck has with the thing it slows down. The bottleneck is inside the process, at a stage within it, or pointed toward an outcome — never "of" it.

Practice scenarios

Practice choosing the right preposition in situations like:

• locating a bottleneck inside a broader workflow ("in")
• pinning a bottleneck to one specific stage ("at")
• connecting a bottleneck to a growth or scaling outcome ("to")

Useful practice phrases:

• "A bottleneck in [the process]."
• "A bottleneck at [the stage]."
• "The bottleneck to [outcome] is [constraint]."