[General] Formal Letter

My question is that in a formal letter is it better to write "Dear Sir" OR "Respected Sir"; likewise is it better to end by saying Respectfully [name], or Faithfully [name]?
Thank you very much!

[Anglika]

In the UK and the US "Dear xxxx" is the normal greeting. The alternative you offer now obsolete in most places.

In the UK the preferred form of ending is "Yours faithfully/sincerely" - "faithfully" if writing to someone unknown by name; "sincerely" if the person is known to you by name.

[konungursvia]

In the UK, dear is not necessary:

Sir,...

[Anglika]

Originally Posted by konungursvia

In the UK, dear is not necessary:

Sir,...

Excuse me, but it is. Sir is very infra dig and not suitable for a formal letter.
Any letter addressed in this manner indicates a complete lack of good training in proper secretarial work. Not uncommon, but not any more acceptable or desirable.

[Tdol]

Plain 'Sir' is used in letter to newspapers, but I would not recommend its use in other formal BrE correspondence.

[konungursvia]

I did not suggest it was better to leave off the word "Dear", only that one frequently observes its absence in the most formal correspondence in the UK. Traditionally, "Dear" has been reserved for personal letters, although the American usage is catching on.

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