off chance
B2Informal to neutral
Definition
Meaning
a slight possibility; an unlikely or improbable event or circumstance
A contingency considered despite low probability, often motivating preparatory action or inquiry just in case
Linguistics
Semantic Notes
Almost exclusively used in the fixed phrase "on the off chance" or "on an off chance." The phrase suggests acting despite low probability, not complete impossibility. It often implies hope or speculative action.
Dialectal Variation
British vs American Usage
Differences
No significant difference in meaning or usage. The phrase is equally common in both varieties.
Connotations
Identical connotations of slight, hopeful possibility.
Frequency
Equal frequency in both dialects. No regional preference.
Vocabulary
Collocations
Grammar
Valency Patterns
[Subject] + [verb of action] + on the off chance + (that) + [clause][Subject] + [verb of action] + on the off chance + of + [gerund/noun phrase]Vocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “on the off chance”
Usage
Context Usage
Business
Used to justify speculative investment, research, or outreach: 'We contacted the start-up on the off chance they were seeking funding.'
Academic
Rare in formal writing but appears in discussions of probability or research methodology: 'The survey included the question on the off chance it revealed a new correlation.'
Everyday
Common in social planning and personal decisions: 'I'll bring an umbrella on the off chance it rains.'
Technical
Limited use, might appear in computing or engineering regarding low-probability contingencies: 'The system includes a backup protocol on the off chance of primary sensor failure.'
Examples
By Part of Speech
adjective
British English
- It was an off-chance meeting that changed everything. (Hyphenated attributive use is rare)
- He took an off-chance gamble.
American English
- It was an off-chance encounter. (Hyphenated attributive use is rare)
- She made an off-chance bet.
Examples
By CEFR Level
- I called him on the off chance he was at home.
- She took a coat on the off chance.
- We dropped by the café on the off chance you'd be there.
- I applied for the job on the off chance they hadn't filled it.
- The detective visited the old warehouse on the off chance of finding new evidence.
- On the off chance that the flight is cheaper tomorrow, I didn't book it today.
- The researcher included the obscure variable in her model on the off chance it proved significant.
- He decided to hedge his investment on the off chance of a sudden market downturn.
Learning
Memory Aids
Mnemonic
Think of a football shot taken from FAR OFF the goal – it has a small chance of scoring. An OFF chance is a FAR-OFF, unlikely chance.
Conceptual Metaphor
POSSIBILITY IS DISTANCE (a remote/off chance), LIKELIHOOD IS PROXIMITY (a strong/near chance).
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Avoid literal translation as 'выключенный шанс' (switched-off chance).
- The phrase corresponds to 'на всякий случай' (just in case) but specifically for low-probability events.
- Do not confuse with 'off-chance' as a single unhyphenated word in some dictionaries; it's almost always a two-word phrase in the idiom.
Common Mistakes
- Using 'in the off chance' (correct is 'on').
- Omitting the article: 'on off chance' (correct is 'on the/an off chance').
- Using it without a following purpose clause: 'I bought a ticket. It was an off chance.' (Incorrect; requires 'on the off chance that I would win').
Practice
Quiz
Which preposition correctly completes the idiom?
FAQ
Frequently Asked Questions
Both are correct. 'On the off chance' is significantly more common, but 'on an off chance' is also used, especially when not referring back to a previously mentioned possibility.
Rarely. It is almost exclusively used in the fixed prepositional phrase. Standalone use ('It's an off chance') is uncommon and may sound awkward.
They are very close synonyms. 'On the off chance' emphasizes the low probability of the event occurring, while 'just in case' is more general and focuses on preparedness for any contingency, likely or not.
It is neutral to informal. It is perfectly acceptable in spoken English and informal writing, but might be replaced with 'in the unlikely event that' or 'contingent upon the possibility of' in very formal or legal documents.
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