Sorry - this is a bit off topic. Can't find this simple info anywhere on the web!

What is the correct format for a UK number on a biz card so folks can call you from abroad?

I think that officially it's:

+44 20 7123 4567

But I don't want to have to put that and:

020 7123 4567

...for UK callers.

BT put both on their contacts page - and assume (most proberbly wrongly!) that they must be technically correct.

So is this the non-standard, standard?:

+44 (0)20 7123 4567

Thanks, sorry about posting here my site Admin 

Yup, this 3 4 4 layout has been raised elsewhere, with a nod to the US's 3 3 4. I think that we might aim for 07X XXXX XXXX for mobiles, now that there is portability and one can not know the likely charge until the fifth or sixth dialled digit.
And it matches 02X XXXX XXXX for those areas outside London (lest you think that I am too London-centric   ).
And, of course, we could then have 09X for PRS. The joy of watching one of the Dimblebys struggling with Question Time's 09011 114 411 - when it appears that some one very bright actually went for 090 1111 4411.

Well, yes and no. If we go for a closed numbering and dialling plan (and so no local dialling) then the numbers dialled are the same, but a high proportion of calls (it used to be 49% - I hope to be able to check) are still dialled without the code.

But I was also thinking of the ease of remembering and storing digits. Or is that a reflection of my age? (aging?) The regular pattern and layout do help to reduce errors in dialling.