Hello vs Hey

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

Hello

High-frequency chunk A1

Hey

Informal Top 1,000 (very common) A1 exclamation

Most formal: Hello

	Hello	Hey
Pronunciation	🇬🇧 /["/həˈləʊ/"]/ 🇺🇸 /["/həˈləʊ/"]/	🇬🇧 /["/heɪ/"]/ 🇺🇸 /["/heɪ/"]/
Meaning	A word used to greet someone.	A casual greeting used to say hello.
Example	Hello John, how are you?	Hey, can I just ask you something?
Register	Neutral	Informal
How common	High-frequency chunk	Top 1,000 (very common)
CEFR level	A1	A1
Part of speech		exclamation
Collocations	say hello, hello there, hello everyone, hello friend, hello world	say hey, hey there, hey buddy, hey dude
Antonyms	goodbye, farewell	goodbye, farewell, bye
Common mistakes	Using 'hello' in overly formal situations., Confusing 'hello' with 'hi' for informal contexts., Not varying the greeting based on time of day.	Using 'hey' in formal emails or letters., Spelling it as 'hay' when greeting someone.
Usage notes	Use 'hello' in most situations when greeting someone. It's suitable for both formal and informal contexts. Avoid using in very formal settings where a greeting like 'good afternoon' might be more appropriate.	Primarily used in informal situations among friends or acquaintances. It's less appropriate in formal contexts or professional settings. Avoid using it with people you don't know well.

See it in real clips

Top Gear › S1 E1

Hello.

Stranger Things › S1 E1

- MIKE: You’re disgusting! - Hello?

Top Gear › S1 E1

Hello.

Stranger Things › S1 E1

- MIKE: You’re disgusting! - Hello?

Hello

Succession › S1 E1

Hey!

Hey

Frequently asked questions: Hello vs Hey

What's the difference between Hello and Hey?

Hello: A word used to greet someone. Hey: A casual greeting used to say hello.

Which is more formal: Hello and Hey?

Hello is the most formal of these.

Are Hello and Hey the same CEFR level?

Hello: A1, Hey: A1 on the CEFR scale.

Can you show an example of each?

Hello: Hello John, how are you? Hey: Hey, can I just ask you something?

Can I use Hello and Hey interchangeably?

Not always. Hello and Hey 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.