"Confirm in return" or "Confirm by return"
I am writing a letter to my vendor and I need them to reply to my letter. I see the 2 above phrases.

Which one is correct?

Thanks

Question

"Confirm in return" or "Confirm by return"
I am writing a letter to my vendor and I need them to reply to my letter. I see the 2 above phrases.

Which one is correct?

Thanks

Answer

I will use not use the both above .I would say, 'Kindly acknowledge this mail by replying"

Answer

Is this a multiple choice answer.  Both answers are less than  ideal.   Confirm by return " something , like email or mail "  would be the answer.  So by, is the best choice.

Answer

Confirmation returning