Korean "Have To": -아/어야 하다 and 해야 돼요 Explained
Learn how to say "have to" and "must" in Korean with -아/어야 하다 and -아/어야 되다, from 가야 해요 to 해야 했어요, plus how to say "you don't have to".
BeginnerWant, can, must7 min readTap any Korean word to see it explained
The short answer
To say “have to” or “must”, add 아야 해요 or 어야 해요 to a verb stem: 가야 해요 (I have to go), 먹어야 해요 (I have to eat). 해요 can be swapped for 돼요 with no change in meaning: 가야 돼요.
The ending 아/어야 means “only if”. So 가야 해요 is literally “only if I go, it works”. In other words: I have to go. If you already know the present tense 아요/어요, you already know how to pick 아 or 어. Tap the chips below to see each part.
1. Verb + 아/어야 해요
Use the same vowel rule as the present tense. If you can say 가요, you can say 가야 해요. If you can say 먹어요, you can say 먹어야 해요. Just swap 요 for 야 해요.
- Last vowel is ㅏ or ㅗ: add 아야. 가다 becomes 가야 해요.
- Any other vowel: add 어야. 먹다 becomes 먹어야 해요.
- 하다 verbs: 하다 becomes 해야. 공부하다 becomes 공부해야 해요.
Korean 'eats' medicine: 약을 먹다 means to take medicine.
2. 해야 해요 or 해야 돼요?
You will hear 돼요 (from 되다) in place of 해요 all the time. The meaning is the same. In casual chat, 돼요 is probably the more common one. Both are correct, so use whichever comes out first.
Literally 'By what time do I have to come?'
| Dictionary form | Have to | Had to |
|---|---|---|
| 가다 (go) | 가야 해요 | 가야 했어요 |
| 오다 (come) | 와야 해요 | 와야 했어요 |
| 먹다 (eat) | 먹어야 해요 | 먹어야 했어요 |
| 마시다 (drink) | 마셔야 해요 | 마셔야 했어요 |
| 기다리다 (wait) | 기다려야 해요 | 기다려야 했어요 |
| 쓰다 (write) | 써야 해요 | 써야 했어요 |
| 하다 (do) | 해야 해요 | 해야 했어요 |
| 일하다 (work) | 일해야 해요 | 일해야 했어요 |
3. Had to: 아/어야 했어요
For the past, leave 아/어야 alone and put the past tense on the last word: 해요 becomes 했어요, and 돼요 becomes 됐어요.
4. Don’t have to: 안 -아/어도 돼요
Careful here. “Don’t have to” does not use 아/어야. Instead, Korean says “it’s okay even if you don’t”:
- Short form: 안 + verb + 아/어도 돼요. 안 가도 돼요 (you don’t have to go).
- Long form: stem + 지 않아도 돼요. 가지 않아도 돼요. Same meaning, a bit more careful.
Hear it in songs
Love songs are full of “I have to let you go” and “I have to forget you”. Look for 야 해 at the end of a line. Open a song in Hanbok Lyrics and tap a line to see every ending explained. Next, learn how to say “can” with -(으)ㄹ 수 있다, or review the vowel rules in the Korean present tense.
Check yourself
Quick check · 1 of 4먹다 (eat) + "have to" = ?
The last vowel in 먹 is ㅓ.
Questions learners ask
How do you say "have to" or "must" in Korean?
Add 아야 or 어야 to the verb stem, then 해요 or 돼요: 가야 해요 (I have to go), 먹어야 해요 (I have to eat). For 하다 verbs it becomes 해야 해요 (I have to do it).
What is the difference between 해야 해요 and 해야 돼요?
They mean the same thing: "I have to do it." 해야 돼요 is very common in everyday speech. 해야 해요 is just as correct and a little more common in writing. Use whichever you like.
How do you say "you don't have to" in Korean?
Use -지 않아도 돼요, or the short form 안 -아/어도 돼요. Both mean "it's okay not to": 안 가도 돼요 (you don't have to go), 걱정하지 않아도 돼요 (you don't have to worry).
How do you say "must not" in Korean?
Not with 아/어야. Use -(으)면 안 돼요, which literally means "if you do it, it is not okay": 여기서 사진 찍으면 안 돼요 (You must not take photos here).