You can use 반말, casual speech, with close friends of about your own age, with younger people you know well, and inside the family, and with a new acquaintance only after they have invited it, usually with the words 말 편하게 해요. With everyone else, strangers, staff, teachers, colleagues and anyone older, you keep the polite -아요/어요 endings, however friendly the conversation gets.
That is the short answer, and the second half of it matters more than the first. Learners tend to ask "when can I use 반말" as a question about age. In Seoul it is a question about permission, and age is only one of the things that decide who gives it.
What 반말 is, in one table
The form is the easy part. Take the polite -아요/어요 form and drop 요: 가요 becomes 가, 먹어요 becomes 먹어, 공부해요 becomes 공부해. Tenses keep their shape, 갔어요 becomes 갔어, and a question is the same words with a rising tone. Nouns are the one exception: 이에요/예요 becomes 이야 after a 받침 and 야 after a vowel, and 아니에요 becomes 아니야. A few everyday words change with it.
| Polite | Casual (반말) | Note |
|---|---|---|
| 가요 · 먹어요 · 공부해요 | 가 · 먹어 · 공부해 | drop 요 |
| 갔어요 · 먹을 거예요 | 갔어 · 먹을 거야 | tenses stay |
| 학생이에요 · 친구예요 | 학생이야 · 친구야 | 이야 after a 받침, 야 after a vowel |
| 아니에요 | 아니야 | |
| 네 · 아니요 | 응 (어) · 아니 | |
| 저 · 제가 · 제 | 나 · 내가 · 내 | 'you' is 너, but friends often use the name |
| 같이 가요 · 갑시다 | 가자 | 'let's' |
| 가지 마세요 | 가지 마 | 'don't' |
| 유나 씨 | 유나야 · 지민아 | calling a friend: 야 after a vowel, 아 after a 받침 |
- 뭐 해? — 밥 먹어.What are you doing? — Eating.2B
- 떡 샀어? — 응, 샀어.Did you buy the rice cakes? — Yes, I did.2B
- 이거 뭐야? — 고추장이야.What's this? — It's gochujang.2B
- 나는 학생이야. 너는?I'm a student. And you?2B
- 학생이야. I'm a student.
- 떡 샀어? Did you buy the rice cakes?
- 같이 만들자. Let's make it together.
- 아니야. No, it isn't.
Who it is safe with
Think of three circles.
Close friends about your age. This is the circle 반말 was made for. Between university friends, roommates, people you met at a language exchange and now see every week, 반말 is normal, and staying in -아요/어요 for months can start to feel like you are keeping them at a distance. Even here it begins with a moment: one of you says 우리 말 편하게 해요, or 말 놓을까요?, and the other agrees. In Seoul that moment often comes early, sometimes in the first conversation after people have compared ages, and sometimes it never comes, because one of the two prefers to keep it polite. Both are fine.
Younger people you know well, and family. A younger cousin, a friend's little brother, the students you tutor. Many Korean children speak 반말 to their parents too. If a younger person speaks politely to you and you answer in 반말, that is the expected pattern, not rudeness.
Everyone else: never first. Strangers, shop and cafe staff, your teacher, your boss, colleagues, your friend's parents, and anyone older than you, even by a year, even if they have started using 반말 with you. The grammar page says it in one line, and it is the line we would carve above every classroom door: never start 반말 yourself; wait until you hear 말 편하게 해요.
- 우리 말 편하게 해요.Let's talk casually.2B
- 말 놓을까요? — 네, 좋아요.Shall we drop the formal speech? — Yes, let's.2B
- 밥 먹었니? — 네, 먹었어요.Have you eaten? — Yes, I have.2B
The last example is the one learners miss. When an older person speaks 반말 to you, the question 밥 먹었니? is warm, not a signal to match them. You answer politely, 네, 먹었어요, and that is the correct exchange from both sides.
How Koreans ask, and how you can
The invitation is usually short and comes from the person who is older or more senior, or from either side when the two are the same age. You will hear:
- 말 편하게 해요. "Speak comfortably." The most common one.
- 말 놓으세요. "Put the formal speech down." Said to the older person, offering them the right to be casual with you.
- 우리 말 놓을까요? "Shall we both drop it?" Between people of the same age.
Can you ask? Yes, if you are the same age or older, and if the other person is a friend rather than a colleague. The safe form for a learner is the question, 우리 말 편하게 할까요?, because it leaves the other person free to say "a little later". If they answer 네, you switch together. If they keep using -아요/어요 after that, follow them back; some people agree out of politeness and then show you what they prefer.
- 유나 씨도 스물세 살이에요? 저도요.You're twenty-three too? So am I.
- 그럼 우리 말 편하게 해요.Then let's talk casually.
- 좋아. 주말에 뭐 해?Sure. What are you doing at the weekend?
- 친구 만나. 같이 갈래?Meeting a friend. Want to come?
- The grammar page for casual speech read on a phone: the forms, the words that change, how to call a friend, and the one rule about who starts.
What we see in class
Students ask about 반말 in their first month, long before Level 2B, because it is what they hear in dramas and what their Korean friends use with each other. We teach it in Level 2B on purpose, and the reason is not that the forms are hard. Dropping 요 takes an afternoon. The hard part is judgment, and judgment needs a year of listening to Koreans decide, in front of you, who gets 반말 and who does not.
The mistake we see most is not grammar. It is a student who was spoken to in 반말, by a shop owner, an older classmate, a host family's parent, and took it as permission. In Korean, 반말 going one way is normal and says nothing about what should come back. The second mistake is the mixed sentence: 저는 학생이야, with the polite 저 and the casual ending, or 나는 학생이에요, the other way round. Korean listeners notice the mismatch at once. The pronoun and the ending travel together: 저 with 요, 나 without.
What did not work for us was teaching the two levels side by side early on, so that students could "choose". They did not choose; they mixed. What works is the order on our own pages: the polite endings until they are automatic, then, in Level 2B, 반말 as a form you understand when it is aimed at you, answer politely, and use yourself only once a specific person has invited it. In class we practise the invitation itself, the little exchange of 말 편하게 해요 and 좋아요, because it is the part students never rehearse and the part that decides everything.
Our grammar page explains the forms and the words that change, and the practice set in lesson 10 of Level 2B drills them. Neither page can tell you whether the person in front of you wants 반말. Only they can, and now you know what the invitation sounds like.
Questions people ask
Can I use 반말 with Koreans younger than me that I have just met?
Not on the first meeting. Age gives you the right in principle, but Koreans themselves rarely use it with a stranger who happens to be younger; a shop clerk or a new colleague who is younger still gets -아요/어요. Use 반말 with a younger person once you actually know them, and once they have settled into speaking politely to you.
My Korean friend uses 반말 with me but I still use 요. Is that strange?
It is a little lopsided if you are the same age, and your friend may be waiting for you to join them. Ask: 저도 말 편하게 할까요? If the friend is older than you, the lopsided version is simply correct, and you can keep it as long as you like.
What about online, in messages and comments?
The same rules, with one difference: in comments between strangers, short 반말 is common and is not read as rude. In direct messages with someone you know, follow whatever the two of you use when you speak.