You'd think writing a business letter would be pretty much the same globally. Au contraire!

The differences between UK and US are quite significant.

Initially the UK and US are divided with the return address: in the UK it goes on the right, whereas in the US it can either go on the left or the right.

The recipient's address is left-aligned in both countries (phew, we agree on something!)

Date swiftly follows; the UK date would read: 25th December 2009 on the right or left of the page, and the US: December 25, 2009 always on the left.

Each starts with 'Dear ____'

If you're addressing someone whose name you know: in the US you'd add a fullstop/period after their title (i.e. Mr., Mrs., Ms.) where in the UK we've done away with the point leaving the title thus: Mr, Mrs, Ms

And so we jolly our way on past the surname and...come to a divergence again! In US business letters you'd now enter a colon (:) and in UK letters a comma (,)

i.e. (US) Dear Mr. Jones: / (UK) Dear Mr Jones,

(If you have a subject you want to add, much like the subject line in an email, add it under the salutation. To draw attention both US and UK prefer to use bold and/or upper-case letters)

As we enter the body of the letter, we all agree that, despite following a comma, the line should start with a capital letter . (This is a standard that seems to grate on some German writers composing English letters, who feel that the first letter of the body should be lower case.).

On we stroll though the body of the text where UK and US are in blissful harmony again. Single-line spacing throughout with a blank line (NOT an indent) between paragraphs.

Now you just have to close. In the US, your close should be aligned with YOUR address and in the UK it's always left-aligned.

In the UK, if you know the recipient's name 'Yours sincerely,' is standard, and 'Yours faithfully,' when you don't. 'Kind regards,' and his pleasant variants are acceptable, but they do prefer their cyber domain to paper. In the US, however (thank you, Karen!) the most common closings in a formal letter are 'Sincerely,' 'Sincerely yours,' and 'Very truly yours', ('Cordially' and 'Best regards' also make a show at times).

Leave a few lines (in which to add your signature after printing)... then add your name, and, if you want, your job title.

Job done.

Now, as a little post script, you may want to add ... a post script. In the US, 'PS' or 'ps' is the accepted norm, but in the UK 'p.s.' still holds true.

And there we have it. I hope that helps someone :)