“Can I” or “May I”? Which should we use?
When we ask for, give, and refuse permission, the words we most often use are can and can’t:
- Can I speak to Dave Williams, please?
- You can help yourselves to tea and coffee.
- I’m sorry, you can’t smoke here.
You’ve probably also heard may used in requests and when giving/refusing permission:
- May I take a message?
- Passengers may not leave the airport while waiting for a connecting flight.
So what’s the difference between can and may in requests?
1. May is more formal than can when asking for and giving permission:
- May I speak to Mr Jones, please?
2. We use may when we want to sound more polite:
- May I offer you another drink, sir?
3. We see or hear may, not can, in official announcements, and on signs:
- Hotel guests may use the gym from 6 a.m.
May vs. can = formal vs. informal
Look at the difference between these two signs:
Watch out! Although we very often shorten cannot to can’t, the contraction mayn’t (may not) is rarely used nowadays. Stick with can’t in spoken English when you refuse permission or say that something isn’t allowed.
For more examples, see Grammar rules: modal verbs for expressing permission, or take a look at this British Council page, which has some example sentences.
Feel free to ask questions in the comments below!