Quick answer: “Cost an arm and a leg” means to be extremely expensive; to cost a very large amount of money.
Cost an arm and a leg means to be extremely expensive — so costly that it feels like a massive, even painful sacrifice. The phrase is used when a price is shockingly high, far beyond what seems reasonable. It vividly captures the feeling that you are giving up something precious just to pay for it.
Meaning
When something "costs an arm and a leg", it is not merely expensive — it is excessively so. The idiom conveys genuine shock or complaint at a price. You might use it when buying a car, paying for a medical procedure, booking a hotel room, or purchasing anything where the cost catches you off guard.
The phrase is widely used in both British and American English and is one of the most common idioms for expressing that something is very pricey. It is informal and appears frequently in everyday conversation, reviews, and casual journalism. The hyperbolic image — paying with a limb — emphasises just how extreme the cost feels to the speaker.
Origin and History
The exact origin is uncertain, but the idiom became widespread in the 20th century. It evokes the idea that something is so expensive you would have to sacrifice a limb to pay for it — the ultimate price. One popular (though unverified) folk etymology links it to portrait painting: artists supposedly charged extra for each body part included, so a full portrait with arms and legs was far more expensive than a simple headshot.
Whatever its true origin, the expression gained common currency in English-speaking countries during the mid-20th century and has remained a staple of informal speech ever since. Its vivid, physical imagery makes it instantly memorable and easy to understand, which helps explain its lasting popularity across generations and dialects. Figurative expressions of this kind are the sort of entry catalogued by major reference works such as the Cambridge Dictionary, which track how idiomatic meanings develop and spread.
Examples in Context
| Sentence | Context |
|---|---|
| That designer bag cost an arm and a leg — I can't believe she paid that much. | Shopping, luxury goods |
| Fixing the car cost an arm and a leg; the parts alone were over a thousand pounds. | Car repairs, unexpected expense |
| Private school fees cost an arm and a leg in this city — most families simply can't afford it. | Education, cost of living |
| We loved the hotel, but it cost an arm and a leg, so we're only staying two nights. | Travel, accommodation |
| Healthcare without insurance can cost an arm and a leg in the United States. | Medical costs, systemic commentary |
| He wanted the bespoke suit, but it cost an arm and a leg, so he bought off the rack instead. | Fashion, budget decision |
A Short Dialogue
A: "Did you see those concert tickets?"
B: "Yes — they cost an arm and a leg!"
A: "Front row seats were £500 each."
B: "I'd rather watch it on TV at that price."
Usage Notes
The phrase is always used with a verb of cost or payment: "it cost an arm and a leg", "it will cost you an arm and a leg", "spending an arm and a leg". It is not used as a standalone noun phrase — you would not say "the arm and leg of the ticket".
The idiom is most natural when expressing surprise, complaint, or disbelief about price. It works in both past and present tense: "that cost an arm and a leg" (past purchase) or "it costs an arm and a leg" (ongoing or general fact). The order of the body parts is fixed — always "arm" before "leg".
Common Mistakes
Mistakes to Avoid
The coffee was a little pricey — it cost an arm and a leg.
The coffee was a little pricey — it wasn't cheap. — Reserve "cost an arm and a leg" for things that are genuinely very expensive, not just slightly above average.
Those shoes cost a leg and an arm.
Those shoes cost an arm and a leg. — The fixed phrase is always "an arm and a leg", never reversed.
That holiday was the arm and a leg of prices.
That holiday cost an arm and a leg. — The idiom must follow a cost or spending verb; it is not used as a noun phrase on its own.
Practice
Related Idioms
Practice English Idioms
Use these exercises to master idioms in context:
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Quick Check: Cost an arm and a leg
2 questions — test what you just learned.
1. What does “Cost an arm and a leg” mean?
2. Complete the sentence: “That designer bag _____ — I can't believe she paid that much.”
Frequently Asked Questions
What does "cost an arm and a leg" mean?
"Cost an arm and a leg" means to be extremely expensive — so expensive that the price feels like a huge sacrifice. It is used when something costs far more than expected or more than seems reasonable.
Where does "cost an arm and a leg" come from?
The exact origin is uncertain, but the idiom became widespread in the 20th century. It evokes the idea that something is so expensive you would have to sacrifice a limb to pay for it. Some link it to portrait painting, where adding limbs to a portrait cost extra, though this is unverified.
Can you give an example of "cost an arm and a leg" in a sentence?
"That designer bag cost an arm and a leg." Another example: "Fixing the car cost an arm and a leg — I wasn't expecting a bill that large."
Is "cost an arm and a leg" formal or informal?
It is informal. It is very common in everyday spoken English and informal writing, but in formal or business writing it is better to say "extremely expensive", "prohibitively priced", or "very costly".
What CEFR level is "cost an arm and a leg"?
B1. The meaning is fairly accessible once the idiom is explained, and it appears frequently in everyday conversation about prices and money, making it a useful phrase for intermediate learners.
Is "cost an arm and a leg" positive or negative?
It is negative in tone. It implies that the price is unreasonably high or that the speaker feels the cost is excessive. It often carries a sense of complaint or surprise at the expense.
What are common mistakes with "cost an arm and a leg"?
The most common mistake is reversing the order to "a leg and an arm" — the fixed phrase is always "an arm and a leg". Another mistake is using it for things that are only slightly expensive; it should be reserved for genuinely high costs.
What idioms are similar to "cost an arm and a leg"?
Similar expressions include "cost a fortune", "cost a pretty penny", "break the bank", "set you back a lot", and "highway robbery". All describe something being very expensive or overpriced.
Can "cost an arm and a leg" be used in writing?
Yes, in informal and conversational writing, blogs, reviews, and journalism. For formal reports or academic writing, use "extremely expensive" or "prohibitively costly" instead.
How do I practise idioms like "cost an arm and a leg"?
Think of something you recently considered buying but decided was too expensive. Practise describing it using "cost an arm and a leg", then try LexFizz Flip Tiles to reinforce the phrase in different contexts.