Query

If I am writing to a young gentlemen aged 13, is it correct to address him as Master rather than Mr?

Thank you

Yes, but he may take offence!

Is that form of address still used in the U.K.? It's not at all used in the U.S.

Would someone think you were being deliberately old fashioned, or is it used all the time?

It's really out-dated, but still occasionally used.

Thanks :)