May vs Shall: What Is the Difference & Which Is Correct?

Many English learners confuse may and shall because both are modal verbs, but they serve very different purposes. One is mainly used for permission and possibility, while the other often expresses future intention, offers, or formal obligation. Understanding the difference helps you speak and write English more accurately and naturally.

Comparison Overview

May and shall are both modal verbs in English grammar. They do not change form like regular verbs and are used before the base form of a main verb. While both can appear in formal English, their meanings and functions are different.

May usually shows permission, possibility, or wishes.

Shall usually shows future intention, offers, suggestions, or formal requirements, especially in British English.

Understanding when to use each one improves grammar, clarity, and tone.

Definition of May

May is a modal verb used to express permission, possibility, or polite wishes.

Core meanings of may:
• asking or giving permission
• showing something is possible
• expressing hope or wishes

Examples:
• May I come in?
• It may rain tonight.
• May you live a long life.

Definition of Shall

Shall is a modal verb often used to express future action, offers, suggestions, or formal obligations.

Core meanings of shall:
• talking about future action (especially formal or old-fashioned)
• making offers or suggestions
• stating legal or official rules

Examples:
• Shall we begin?
• I shall return tomorrow.
• The tenant shall pay rent on time.

Main Differences Between May and Shall

Feature	May	Shall
Main meaning	Permission or possibility	Future intention or obligation
Tone	Polite and neutral	Formal or traditional
Common use	Everyday English	Formal English, legal writing
Question use	Asking permission	Making suggestions
Example	May I leave?	Shall we leave?

Key difference:
May asks if something is allowed.
Shall suggests what should happen next.

Usage in Modern English

In modern English, may is still widely used in both spoken and written language.

Shall has become less common in everyday conversation, especially in American English. It remains common in:
• British English
• legal documents
• formal writing
• polite offers and suggestions

Examples:
• American English: Will we start now?
• British English: Shall we start now?

Grammar Guide

Both may and shall are modal verbs.

Basic structure:

Subject + modal verb + base verb

Examples:
• She may go tomorrow.
• We shall meet later.

How Each Term Is Used in Sentences

May
• May I ask a question?
• He may arrive late.
• You may use my pen.

Shall
• Shall we dance?
• I shall call you tomorrow.
• The company shall provide insurance.

Common Mistakes Learners Make

1. Using shall for permission
   ❌ Shall I borrow your book? (possible but unusual)
   ✔ May I borrow your book?
2. Using may for suggestions
   ❌ May we go now? (permission context)
   ✔ Shall we go now? (suggestion context)
3. Confusing formal and informal tone
   Shall sounds more formal than may in many contexts.

Simple Rules to Remember

Use may when:
• asking permission
• talking about possibility
• giving polite wishes

Use shall when:
• making suggestions
• offering help
• writing formal rules

Quick Tips for Writing and Speaking

• Use may in daily conversations for permission.
• Use shall in formal writing or legal documents.
• In American English, will often replaces shall.
• In British English, shall is still common in questions.

When to Use Each One

Use may when:
• asking permission politely
• expressing uncertainty
• giving blessings or wishes

Examples:
• May I sit here?
• She may join us later.
• May God bless you.

Use shall when:
• suggesting an action
• offering to do something
• writing contracts or rules

Examples:
• Shall we eat?
• Shall I open the window?
• Payment shall be due monthly.

When NOT to Use Each One

Do not use may:
• for firm future plans
❌ I may definitely come tomorrow.
✔ I will come tomorrow.

Do not use shall:
• in casual American conversation too often
❌ Shall I text you later? (sounds overly formal)
✔ Will I text you later?

Which One to Use (Decision Guide)

Ask yourself:

Are you asking permission?
→ Use may

Are you talking about possibility?
→ Use may

Are you making a suggestion?
→ Use shall

Are you writing a legal rule?
→ Use shall

Are you speaking casually in American English?
→ Usually use will, not shall

Real World Practical Examples

May Examples

1. Education: May I submit my assignment tomorrow?
2. Daily life: You may take my umbrella.
3. Science: This chemical may react with water.
4. Business: Sales may increase next quarter.
5. Technology: The update may fix the bug.

Shall Examples

1. Education: Shall we review chapter three?
2. Daily life: Shall I make dinner tonight?
3. Science: The experiment shall begin at noon.
4. Business: The company shall reimburse expenses.
5. Conversation: Shall we meet at six?

Self Assessment (Fill in the Blanks)

1. ______ I open the door?
2. ______ we start the meeting now?
3. It ______ rain later today.
4. The contract ______ expire next year.
5. ______ I help you with that?
6. Students ______ submit homework on Friday.
7. She ______ arrive late tonight.
8. ______ we order pizza?
9. You ______ leave after class.
10. The law ______ apply equally to all citizens.
11. He ______ call you tomorrow.
12. ______ I use your phone?
13. We ______ discuss this later.
14. The medicine ______ cause drowsiness.
15. ______ we go for a walk?
16. Visitors ______ not enter this area.
17. I ______ never forget this day.
18. You ______ borrow my notes.
19. ______ I close the window?
20. It ______ snow tonight.

Answers

1. May
2. Shall
3. May
4. Shall
5. Shall
6. Shall
7. May
8. Shall
9. May
10. Shall
11. Shall
12. May
13. Shall
14. May
15. Shall
16. Shall
17. Shall
18. May
19. Shall
20. May

Final Verdict

Both may and shall are useful modal verbs, but they are not interchangeable. Use may for permission, possibility, and polite wishes. Use shall for suggestions, offers, future intention, and formal obligations. If you remember that may asks permission and shall suggests action, choosing the correct word becomes much easier.

Conclusion About May vs Shall

Understanding the difference between may and shall helps you use English more confidently in both speaking and writing. While may focuses on permission, possibility, and polite expressions, shall is more formal and often used for suggestions, future actions, or legal instructions. In everyday communication, may feels softer and more common, whereas shall carries a structured or traditional tone. Many learners confuse them because both are modal verbs, but their purpose is quite different. Once you recognize the context, choosing the right word becomes simple and natural. Practicing real sentences is the best way to master them and avoid common mistakes in daily English usage.

FAQs

What is the main difference between may and shall?

May is used for permission and possibility, while shall is used for suggestions, future actions, or formal rules. May sounds more polite and common in daily English, whereas shall is more formal and traditional, often seen in legal or structured writing.

When should I use may in a sentence?

Use may when asking or giving permission or when something is possible. For example, May I go outside? or It may rain today. It is commonly used in polite communication and everyday conversation.

When is shall commonly used?

Shall is used for suggestions, offers, or formal statements. For example, Shall we begin? or You shall follow the rules. It is more common in British English and formal writing.

Is may more common than shall in modern English?

Yes, may is more commonly used in modern English, especially in spoken language. Shall is less frequent in everyday conversation but still appears in formal writing and legal documents.

Can shall replace will in future tense?

In some cases, shall can replace will, especially in formal British English. However, in modern usage, will is preferred for expressing future actions in most contexts.

Is may used for probability?

Yes, may is often used to show possibility or uncertainty. For example, She may arrive late means there is a chance she will be late but it is not certain.

Can I use shall for asking permission?

It is not common to use shall for permission. Instead, may is the correct and polite choice, such as May I enter the room?

Why is shall less common in American English?

In American English, will has largely replaced shall in everyday speech. Shall is mostly limited to formal writing or very specific polite suggestions.

What tone does may give in communication?

May gives a polite, soft, and respectful tone. It is often used in formal requests, permissions, and expressions of possibility in both spoken and written English.

What is an easy way to remember may vs shall?

Remember that may is for permission and possibility, while shall is for suggestions or formal rules. This simple rule helps avoid confusion in most situations.