25 Common English Idioms for Everyday Conversation (and Which Ones Sound Old-Fashioned)

An idiom is a fixed expression whose meaning is different from the meaning of its individual words: "break the ice" has nothing to do with ice; it means making people feel relaxed when they first meet. Below are 25 common English idioms that people still use in everyday conversation today, each with its meaning and a natural example, plus a list of idioms that learners often study but that now sound old-fashioned or overused. The idioms here are an everyday selection chosen for usefulness, not a ranking by frequency. Meanings were checked against the Cambridge Dictionary. If you learn these 25 and use them in the right situations, your English will sound more natural without sounding forced.

What an idiom is (and how it differs from a phrasal verb)

An idiom is a group of words with a meaning you usually cannot guess from the words alone. A phrasal verb is a verb plus a particle (give up, look after). Some phrasal verbs are idiomatic, but most idioms are longer, fixed phrases. You cannot normally change the words in an idiom: "break the ice" works, but "break the snow" or "smash the ice" does not.

For phrasal verbs, see our separate guide to common phrasal verbs for everyday conversation.

Idioms for social situations and feelings

Idiom	Meaning	Example
1. break the ice	make people feel more relaxed when they first meet	"Let's start with a quick game to break the ice."
2. under the weather	feeling slightly ill	"I'm a bit under the weather today, so I'll work from home."
3. on cloud nine	extremely happy	"She's been on cloud nine since she got the job."
4. get cold feet	suddenly become too nervous to do something you planned	"He got cold feet and cancelled the presentation."
5. let off steam	do something to release strong feelings or energy	"I go running after work to let off steam."
6. on the same page	agreeing or understanding something in the same way	"Before we start, let's make sure we're all on the same page."

Idioms for work and getting things done

Idiom	Meaning	Example
7. get the ball rolling	start an activity or process	"I'll send the first draft to get the ball rolling."
8. call it a day	stop working for the day	"We've done enough. Let's call it a day."
9. cut corners	do something badly or cheaply to save time or money	"Don't cut corners on safety checks."
10. hit the nail on the head	describe a problem or situation exactly right	"You've hit the nail on the head: the real issue is the budget."
11. back to square one	back to the beginning after a failed attempt	"The client rejected the design, so we're back to square one."
12. in the loop / keep someone in the loop	informed about what is happening	"Please keep me in the loop about the schedule."
13. a learning curve	the process of learning something new, often difficult at first	"The new software has a steep learning curve."

Idioms 6, 7 and 12 are especially common in meetings and emails. For more workplace language, see our guides to business English and writing work emails.

Idioms for everyday life and decisions

Idiom	Meaning	Example
14. a piece of cake	very easy	"The test was a piece of cake."
15. cost an arm and a leg	be very expensive	"Rent in this city costs an arm and a leg."
16. once in a blue moon	very rarely	"I only eat fast food once in a blue moon."
17. sleep on it	wait until the next day before making a decision	"It's a big offer. Can I sleep on it?"
18. the last straw	the final problem that makes a situation unacceptable	"The third delay was the last straw, so we changed suppliers."
19. hit the road	leave, start a journey	"It's getting late. We should hit the road."
20. better late than never	it is better to do something late than not at all	"I finally started learning English at 45. Better late than never!"

Idioms for conversations and opinions

Idiom	Meaning	Example
21. it's not rocket science	it is not difficult to understand	"Just follow the instructions. It's not rocket science."
22. beat around the bush	avoid saying something directly	"Stop beating around the bush and tell me what happened."
23. on the fence	unable to decide or choose a side	"I'm still on the fence about which course to take."
24. a long story short / to cut a long story short	to give only the main point	"To cut a long story short, we missed the flight."
25. speak of the devil	said when the person you are talking about appears	"Speak of the devil, here's Tom now!"

"To cut a long story short" is the common British form; "long story short" is common in American and informal speech.

Idioms that can sound old-fashioned or overused

Many idiom lists for learners include expressions that native speakers rarely use in normal conversation today. They are not wrong, and you will still meet them in books, films and jokes, but using them seriously can make you sound like a textbook or someone from another generation. The labels below are our editorial judgement unless a dictionary label is mentioned.

Idiom	Meaning	Why to be careful	Say instead
the bee's knees	excellent	Cambridge Dictionary labels it "old-fashioned, informal"	"It's brilliant / amazing."
it's raining cats and dogs	it's raining heavily	Well known but often heard as a cliché or a joke in everyday speech	"It's pouring (down)."
the cat's pyjamas / whiskers	excellent	Dates from the early 20th century; rarely used seriously today	"It's fantastic."
as right as rain	completely well again	Still understood, but sounds dated in most contexts	"I'm fine now / fully recovered."
full of beans	full of energy	Used mostly about children, often by older speakers	"She's got so much energy."
a stitch in time saves nine	fix a small problem early to avoid a bigger one	A proverb; sounds formal or old-fashioned in conversation	"Better to fix it now before it gets worse."

Usage changes over time and between regions, so you may hear some of these in certain communities. The safe rule is: understand them, but use the "say instead" option in your own speech.

How to use idioms naturally (and when not to)

• Use one at a time. A sentence with three idioms sounds unnatural. One idiom in a conversation is usually enough.
• Keep the exact words. Idioms are fixed: "cost an arm and a leg", not "cost a hand and a leg".
• Change the verb tense, not the idiom. "She got cold feet", "He's getting cold feet", "Don't get cold feet!" are all correct.
• Check the register. Most idioms in this list are informal or neutral. In formal writing (reports, academic essays, IELTS Writing Task 2), plain language is usually better: write "very expensive" rather than "cost an arm and a leg".
• Be careful in international settings. If you speak English with other non-native speakers, idioms can confuse people. "Let's start" is clearer than "let's get the ball rolling" when the group's English levels are mixed.

Practice: complete the sentences

Choose an idiom from the list to complete each sentence. Answers are below.

1. "I can't decide yet. Can I ___ and tell you tomorrow?"
2. "The new phone ___. I can't afford it."
3. "I'm feeling a bit ___. I think I'm getting a cold."
4. "We're all tired. Let's ___."
5. "She was ___ after she passed her exam."
6. "I only see my cousins ___ because they live abroad."

Answers: 1. sleep on it; 2. costs an arm and a leg; 3. under the weather; 4. call it a day; 5. on cloud nine; 6. once in a blue moon.

For a much larger reference, download our free English Idioms & Phrasal Verbs PDF, which explains 500+ expressions with register labels. To learn idioms as part of natural word combinations, see our guide to learning vocabulary in chunks and our free lessons.

What this article cannot tell you

• Exact frequency. We did not use corpus data to rank these idioms; they are a practical selection of expressions commonly heard in everyday British and American English.
• Every regional variation. Some idioms are more common in British English, others in American, Australian or South African English, and some have different forms in each.
• Whether an idiom fits your situation. Tone depends on who you are talking to. When in doubt, ask a teacher or a native-speaking friend, or get feedback in one of our Conversation courses.