Several of my English students have asked me “Should I use HAVE TO or MUST?” I made this Grammar Guide and Infographic to help answer this question.
Have to and must are both used to show that something is necessary, but there are some differences.
HAVE TO can be used in the past tense (HAD TO do something) while MUST can not.
The negative forms have a different meaning. MUST NOT do does not equal DON’T HAVE to do.
HAVE TO do is more common in North America than MUST do.
Let’s understand how to use these words with some with natural English examples, short audio, and a simple quiz. Also you can find a custom info-graphic at the bottom of this post.
Have/Has to do (something)
If we have to do something it means it is necessary, we are required to do it.
I have to work this Saturday.
Everyone has to work this Saturday.
[It is necessary to work on Saturday, we are required to work on Saturday.]
Wally broke his leg on Tuesday. He had to go to the hospital.
[It was necessary for Wally to go to the hospital.]
He has to wear a cast for 6 weeks.
[He is required to wear a cast for 6 weeks.]
I have to finish this report today or my boss will be so angry!
[It’s necessary to finish this report. If I do not finish the report by the end of the day my boss will get mad.]
MUST do (something)
Must can be used in the same way as have to.
It’s getting late, I must go. – This means the same as:
It’s getting late, I have to go.
Must can be used to give your opinion or recommendation.
I watched that new horror movie last night. It’s great! You must watch it.
= I (strongly) recommend that you watch the new horror movie. (In my opinion.)
I watched that new horror movie last night. It’s great! You have to watch it. – This is also natural.
I’m having a big party this weekend, you must come!
*The grammar is correct, but for me, it’s unusual. I did some research and according to the website https://www.tofluency.com. “Have to is more common, especially in North America.” That’s why it is not usual for me. 😉
I’m having a big party this weekend, you have to come!
*This is more natural for me.
Should I use Have To or Must? Grammar
As I stated above, have to is more common in natural conversation. (For me as a Canadian native speaker.) Both are okay and the meaning is the same.
Either expression can be used to give your opinion, but when we talk about a fact rather than an opinion we use have to.
Here is an example:
I have to take a 70-minute train ride to work every day.
*This is a fact, not my opinion.
must take a 70-minute train ride to work every day.) This is not correct.
Have to/has to is changed to had to when we talk about a past necessary action.
I had to wait 30 minutes for the bus today.
We don’t use must for the past tense.
Must is usually used when rules or instructions are written, not spoken.
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Below you can find some other examples where you need to use have to.
Have To examples with questions and negative sentences
We ask questions or make negative sentences with HAVE TO using do/does/did. Please look at the following examples:
Do you have to work on Saturday?
Does Byron have to work on Saturday?
Did you have to work last Saturday?
I don’t have to work on Saturdays.
(Saturday is plural in this sentence because the speaker means Saturdays in general. For example, I don’t have to work this Saturday or next Saturday and I didn’t have to work last Saturday or Saturday the week before.)
I didn’t have to work last Saturday.
A: Why did Pete have to work late last night?
B: He didn’t have to, he just wanted to miss the rush hour traffic so caught up on some emails.
HAVE TO with WILL
We can use have to with WILL to show a necessary future action.
If Wally’s leg doesn’t heal soon he will have to miss the playoffs.
I hope I can finish this report by Friday, I will have to work on Saturday if I don’t.
My sport coat ripped at work today. I‘ll have to buy a new one this weekend.
HAVE TO with MAY/MIGHT
We can use have to with MAY/MIGHT to show that something is possible.
The boss hasn’t decided yet but we might have to work on Saturday. I hope we don’t!
[It’s possible that we will have to work on Saturday.]
I want to go to your baseball game on Saturday, but I may have to miss it due to work.
[It’s possible that I cannot go to your game because I may work on Saturday.]
There was a big storm at the resort last Sunday and the hotel was damaged. I might have to reschedule my vacation if they can’t get it fixed before my trip.
[It’s possible that I have to change my vacation dates because the resort I was planning to stay at was damaged by a storm.]
Negative – Don’t Have To and Must Not (Grammar)
The meaning for the negative forms of have to and must are completely different.
Must not = Do not or Can not (It is necessary that you don’t do it.)
We are having a surprise party for Dominic this Saturday. Please invite as many people as you like but Dominic must not find out.
[Do not tell Dominic, he can’t know about the party.]
I’d better wake up early tomorrow. It’s my first day at a new job so I must not be late.
[I cannot be late on my first day. That would be so terrible!]
Don’t Have to = You don’t need to do something, but if you want to it’s okay.
Tomorrow is my day off. I don’t have to wake up early!
[Of course, you can wake up early if you want to. But it’s not necessary. You can sleep in!]
Have got to
It’s okay to say have got to.
Unfortunately, I’ve got to work this Saturday.
Wally’s leg looks bad. He has got to go to the hospital.
Have to/Have got to Pronunciation
Have to is spoken like hafta in casual conversation. HAFTA
My wife’s mom is coming to see our apartment tomorrow so we hafta clean up tonight.
My mobile phone company raised their monthly fee again! I hafta change companies.
[This is something I feel strongly about doing. It’s my opinion that I must do it.]
We hafta sign in as soon as we get to the office.
[We are required to sign in when we arrive at work.]
I want to mount our new TV in the living room, but I need to drill 6 holes in the wall. My roommate said we hafta check with the building manager before we do any renovations.
[It is necessary to ask the building manager if we can drill holes in the wall of our apartment.]
VOCABULARY mount [verb] to fix something into position on something, so that you can use it, look at it or study it
Check out the definition for mount at Oxford Learner’s Dictionaries here
Got to is often spoken as the contraction gotta. The first vowel sound is more like an AH when spoken. GAHTTA
It’s getting late. I gotta get some sleep.
[I need to sleep.]
Unfortunately, I’ve gotta work this Saturday.
In casual speech, it is common to drop the have or ‘ve when speaking in the first person. (I have – I’ve We have – We’ve)
Unfortunately, I gotta work this Saturday.
We gotta win tomorrow’s game if we want to make it to the playoffs.
[Our team (we) need to win the game tomorrow.]
*The contraction gotta is also used for the words GOT A.
My bike gotta flat tire on the way to the store.
[My bike got a flat tire.]
I’m going to stay home tonight, I’ve gotta terrible headache.
[I have a bad headache.]
Listen to the Have To or Must Grammar examples from above with this quick AUDIO
You can understand the difference between the contractions GOT TO and GOT A by the grammar of the sentence.
Have got to will be followed by a verb.
I’ve gotta go to school on Sunday for rugby practice. (GO is a verb)
[I have got to go to school.]
Have got a will be followed by a noun.
We practiced in the hot sun for 3 hours. I gotta sunburn on my arms and neck. (SUNBURN is a noun)
[I got a sunburn during rugby practice.]
Have To or Must Grammar – QUIZ
If you have some paper I suggest writing this QUIZ down yourself. When you take the time to write it down, the information is written in your head too! If you read it, write it, and listen to it, the grammar will be easy to use in the future!
1. We just bought a new washing machine and it has many settings. I wanted to wash my sweater yesterday but I didn’t know which setting to use. My wife ___ ___ show me.
2. My cousin from Spain is coming to visit us next week. You _____ meet him! He’s really funny.
3. It started raining after lunch so we ___ ___ close the windows.
4. The concert is free! You ___ ___ to pay for a seat.
5. Alice’s eyes are not so strong. If she wants to read a newspaper she ___ ___ wear glasses.
6. The elevator in my apartment is broken so I ___ ___ use the stairs. I live on the 12th floor!!!
Answers with audio HERE
Info-graphic – PIN it!