how to give regards to someone

Question

I have been told by a (male) person A to give his regards to a (male) person B. I don't know them too well, but I have met them both semi-privately (person A is a coworker of a friend of mine and we have spent a day hiking; person B is an ex-coworker of mine and we had lunch together every now and then), so there is no need to be too formal. They know each other as (ex-)colleagues as well.

How do I do that?

Here are some thoughts of mine; please comment on their correctness, commonness and level of formality/informality. Please also give suggestions.

"Hello B, ...

1. "... best regards from A!"
2. "... I am supposed to send A's regards to you!"
3. "... hello from A!"
4. "... I met A recently and he told me to say hi to you from him!"

Answer 1

They seem okay, but there are better options. For 4, I prefer for him instead of from him since for is used when you do something on someone else's behalf.

Anyway, two more idiomatic phrases, in my opinion, are

1. A sends his regards.
   Example: I met A recently and he sends his regards.
2. A says hello.
   Example: I met A recently and he says hello.

1 sound more formal. 2 is casual. As J.R. points out, 1 could be too formal for some everyday conversations. Considering your situation, I think they are both possible. If you want to sound more casual or friendly, use 2.

Answer 2

Item 1 might be ok in a letter. I would nix 2 and 3. 4 looks the best, but I would change it: "... I met A recently and he asked me to send you his best wishes!"

However, there is this: A sends his regards.

(For example: I met A recently and he sends his regards.)

These seem crude to me. Try:

A asked me to offer you his regards.

I met A recently, he says he knows you, and that I should offer you his regards.