May and might are modal verbs commonly used to talk about possibility, permission, suggestions, and uncertain situations. Because their meanings often overlap, learners may find it difficult to decide which one fits a particular sentence.
In many situations, may and might are interchangeable when expressing possibility. However, there are also contexts in which one form is more natural or grammatically appropriate than the other. Understanding these patterns will help you use both modal verbs more accurately.
What Do May and Might Mean?
May and might are modal auxiliary verbs. They do not change according to the subject, and they are normally followed by the base form of a verb without “to.”
The basic structure is:
S + may/might + base verb
Examples:
- She may join us later.
- They might arrive before noon.
Both sentences express possibility rather than certainty. The speaker believes that the event is possible but does not know whether it will actually happen.
Like other modal verbs, may and might do not take -s with third-person singular subjects.
Example: Incorrect: She may goes home early. → Correct: She may go home early.

How to Use May and Might
May and might have several important functions in English. Their most common use is to express uncertainty, but they can also appear in formal permission requests, suggestions, reported speech, and past deductions.
Use May and Might for Present or Future Possibility
Both may and might can describe something that is possible in the present or future.
Structure:
S + may/might + base verb
Examples:
- It may rain this afternoon.
- Jack might come to the party tonight.
- She may know the answer.
- We might need more time to finish the project.
Some grammar explanations present may as suggesting a somewhat stronger possibility than might. However, this is not a fixed rule. In everyday English, the two forms frequently overlap, and context, tone, and the speaker’s intention can affect the degree of certainty.
Therefore, learners should avoid assigning exact percentages of probability to may and might.
Use May and Might With Actions in Progress
When the possible situation is happening around the present time, may or might can be followed by be + V-ing.
Structure:
S + may/might + be + V-ing
Examples:
- Tom may be working at the moment.
- They might be waiting outside.
These sentences show that the speaker is making an uncertain guess about an action that may currently be in progress.
Use May Have and Might Have for Past Possibility
To make a guess about something that possibly happened in the past, use:
S + may/might + have + past participle
Examples:
- Sarah may have forgotten the meeting.
- He might have taken the wrong bus.
- They may have left before we arrived.
In these cases, the event happened, or may have happened, before the present moment. The speaker does not know exactly what occurred.
Important note: Do not use may/might + past simple to form this meaning.
Example: Incorrect: She might went home early. → Correct: She might have gone home early.
Use May to Ask for or Give Permission
May is commonly used to ask for permission in a formal or polite way.
Structure:
May + subject + base verb?
Examples:
- May I come in?
- May we use this room?
May can also be used to give permission, especially in formal contexts.
Example: You may leave when you have finished the test.
In everyday conversation, can is also widely used for permission, while may tends to sound more formal.
Use Might for Very Formal Permission Requests
Might can also appear in permission questions, although this usage is very formal and less common in everyday conversation.
Examples:
- Might I ask a question?
- Might I make a suggestion?
When answering such a request, English normally does not use might to grant permission. A response such as Yes, you may or simply Yes, of course is more natural.
Use May and Might to Make Polite Suggestions
May and might can soften suggestions, especially with expressions such as may want to, might want to, or might like to.
Examples:
- You may want to check the instructions again.
- You might want to bring a jacket.
- You might like to try a different approach.
Might often makes the suggestion sound more tentative and less direct.
Use Might in Reported Speech
Might can function as the reported form of may when a sentence is shifted into indirect speech.
Example: Anna said, “I may travel next month.” → Anna said that she might travel the following month.
However, might should not simply be treated as the past tense of may in every situation. Both may and might can refer to present and future possibilities.
Use Might in Hypothetical Situations
Might is common when discussing imagined, conditional, or less certain situations.
Examples:
- If I had more free time, I might learn Japanese.
- If the weather improved, we might go hiking.
Here, might emphasizes that the result depends on a hypothetical condition.

May and Might: What Is the Difference?
Although may and might overlap considerably, several differences can help you choose between them more naturally.
| Situation | May | Might |
| Present or future possibility | Common | Common |
| Degree of certainty | Can sound slightly more likely in some contexts | Can sound more tentative in some contexts |
| Formal permission request | Common | Possible but very formal |
| Giving permission | Common in formal English | Normally not used |
| Reported form of “may” | Not normally used after backshifting | Common |
| Hypothetical situations | Possible in some cont exts | Particularly common |
| Polite suggestion | Common with expressions such as may want to | Common and often more tentative |
The core difference is not a strict probability rule. For ordinary present and future possibilities, either verb may be acceptable.
Examples:
- She may come later.
- She might come later.
Both mean that her arrival is possible. The sentence with might may sound slightly more uncertain to some speakers, but the distinction is often small.
May Not vs. Might Not
The negative forms are may not and might not. When they express possibility, they mean that something possibly will not happen or is possibly not true.
Examples:
- He may not attend the meeting.
- The shop might not be open yet.
However, may not can also express prohibition in formal English.
Example: Students may not use mobile phones during the exam.
In this sentence, may not means that students are not permitted to use their phones. Context is therefore important when interpreting the phrase.
Common mistakes when using may and might
- Adding “to” after may or might: Modal verbs take the base form directly. Example: Incorrect: She may to come later. → Correct: She may come later.
- Adding -s to the main verb: The verb after may or might stays in its base form. Example: Incorrect: He might arrives late. → Correct: He might arrive late.
- Using a past-tense verb after might for past possibility: Use might have + past participle. Example: Incorrect: They might left early. → Correct: They might have left early.
- Treating might as an ability verb: Might expresses possibility, not general ability. Example: Incorrect: When I was young, I might swim very fast. → Correct: When I was young, I could swim very fast.
- Assuming may and might always represent fixed probability levels: Their difference in certainty is often influenced by context rather than a precise percentage.
Short Exercise on May and Might
Complete each sentence with may, might, may have, or might have. More than one answer may sometimes be possible.
- It ______ rain later, so take an umbrella.
- Daniel is not answering his phone. He ______ gone to bed.
- ______ I ask you a question?
- If I had more money, I ______ buy a new laptop.
- She said that she ______ join us the following day.
Answers:
- may/might
- may have/might have
- May
- might
- might
See more:
- The Suggest Structure in English: Rules, Usage, and Examples
- English Vowels Explained: Definition, Types, and Correct Pronunciation
May and might are closely related modal verbs used mainly to express possibility and uncertainty. May is also common for formal permission, while might is especially useful in tentative suggestions, hypothetical situations, and reported speech.
Instead of memorizing a rigid probability difference, focus on the grammatical structure and the context in which each modal is used.
Frequently Asked Questions About May and Might
Can may and might be used interchangeably?
Yes, they are often interchangeable when describing present or future possibility, although might can sometimes sound slightly more tentative.
What comes after may and might?
May and might are normally followed by the base form of a verb without “to”, as in may go and might happen.
What is the difference between may have and might have?
Both structures express uncertain past possibility. In many contexts, their meanings overlap, although might have can sometimes sound more tentative depending on the situation.
Keywords:
May might can, could