Say vs. Tell

Say refers to any kind of speech. It is most often used without a personal object.

• She said that she would be late. (NOT She said me that …)

If we want to put a personal object after say, we use to.

Tell

Tell is used to mean ‘instruct’ or ‘inform’. After tell, we usually say who is told.

• She told me that it was my last chance.

Tell can be followed by object + infinitive. Say cannot be used like this.

• I told him to be careful. (NOT I said him to be careful.)

Tell is used without a personal object in a few expressions. Examples are: tell the truth, tell a lie, tell a story/joke.

• Do you think she is telling the truth? (NOT Do you think she is saying the truth?)

Direct and indirect speech

Both say and tell are used with direct and indirect speech. Note that say is more common than tell with direct speech.

• ‘Be careful,’ he said. (OR ‘Be careful,’ he told me. )
• ‘This is your last chance,’ she said. (OR ‘This is your last chance,’ she told me. )

Note that tell is only used to mean ‘instruct’ or ‘inform’; say can refer to any kind of speech.

• She said, ‘Thank you.’ (NOT She told him, ‘Thank you.’)