English UsageComparison guide

Cutoff vs. Cut Off

“Cutoff” is a noun for an ending, limit, point, date, device, or related result and is also used adjectivally. “Cut off” is the verb phrase for stopping, ending, separating, or interrupting.

Quick answer

Use “cutoff” for the noun/adjective and “cut off” for the verb.

Key details

Confusion Familyword-boundary
Rule Familyorthographic-boundary
Termscutoff, cut off

Choose the right form

Decision table for Cutoff vs. Cut Off
If you mean / needUseWhy
a limit, deadline, ending, device, or related thingcutoffIt is the noun and can also be attributive.
the action of stopping, ending, separating, or interruptingcut offIt is the verb.

Further guidance

Core difference

The closed form names or modifies a cutoff; the open form expresses the action.

Fast Test

If you can write “cutting off” or “was cut off,” use the two-word verb.

Sense Boundary

Because both forms have many senses, identify the grammatical role first instead of relying on one definition.

Sources and evidence

Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.

  1. Cutoff — Merriam-Webster (opens in a new tab)Merriam-Webster · Cutoff noun/adjective and cut off verb word-class boundary

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