Act fast vs Hurry up vs Rush

When to use each in English, with meaning, register, and examples.

Act fast

Beyond 10,000 (less common)

Hurry up

InformalTop 2,000 (common)

Rush

Top 1,000 (very common)B2verb
Most common: Rush
 Act fastHurry upRush
Pronunciation🇬🇧 //ækt fæst//🇺🇸 //ækt fæst//🇬🇧 //ˈhʌri ʌp//🇺🇸 //ˈhɜri ʌp//🇬🇧 /["/rʌʃ/","/ˈrʌʃɪz/","/rʌʃt/","/ˈrʌʃɪŋ/"]/🇺🇸 /["/rʌʃ/","/ˈrʌʃɪz/","/rʌʃt/","/ˈrʌʃɪŋ/"]/
MeaningDo something quickly.Do something faster.to move quickly or hurry
ExampleIf you want to win the game, you need to act fast!You need to hurry up or we will miss the train!I had to rush to the station to catch my train before it left.
RegisterNeutralInformalNeutral
How commonBeyond 10,000 (less common)Top 2,000 (common)Top 1,000 (very common)
CEFR level--B2
Part of speechverb
Collocationsact fast in an emergency, act fast to secure a deal, act fast while the offer lastshurry up and wait, hurry up before, hurry up toheadlong, madly, quickly, along, from, into, come rushing, go rushing, rush to somebody’s rescue, headlong, madly, quickly, along, from, into, come rushing, go rushing, rush to somebody’s rescue
Antonyms--slow, dawdle, linger
Common mistakesUsing 'act fast' in a formal context., Confusing 'act fast' with 'act quickly', which has the same meaning but sounds different., Not understanding it implies urgency.Omitting 'up', saying just 'hurry'., 'Hurry up' used in formal writing., Using 'hurry up' without an object or activity.Incorrectly using 'rush' as a noun without an article when needed., Using 'rushed' as a present tense instead of the correct form., Confusing 'rush' with 'push' in the context of moving quickly.
Usage notesUse 'act fast' when you need someone to respond quickly. It's appropriate in many situations, but can sound urgent.Commonly used in casual contexts to prompt someone to act more quickly. Avoid in formal situations.Commonly used when talking about a need to hurry, like catching a bus. Avoid in very formal situations.

See it in real clips

Act fast
Hurry up

Frequently asked questions: Act fast vs Hurry up vs Rush

What's the difference between Act fast, Hurry up, and Rush?

Act fast: Do something quickly. Hurry up: Do something faster. Rush: to move quickly or hurry

Which is more common: Act fast, Hurry up, and Rush?

Rush is the most common in everyday English.

Can you show an example of each?

Act fast: If you want to win the game, you need to act fast! Hurry up: You need to hurry up or we will miss the train! Rush: I had to rush to the station to catch my train before it left.

Can I use Act fast, Hurry up, and Rush interchangeably?

Not always. Act fast, Hurry up, and Rush are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.