DO use them to show omission in quotes (but DON'T change the meaning)

This is the only way you should use ellipses in formal writing: to condense quotes, to save space or cut redundancy or repetition. You'd use an ellipsis to show that you’ve removed part of the original – whether that's a word, a phrase, a sentence or a paragraph.

But to be completely transparent, you need to make sure you’re not changing the meaning of what somebody has said.

Take this remark from former US President Calvin Coolidge, and the often-quoted condensed version:

‘The chief business of the American people is business.’

‘The … business of the American people is business.’

This changes the meaning of his sentence. The original version says that business is the most important concern (implying it's one of several), whereas in the second it sounds as if business is the only important thing.

So just be careful: you are gambling with your reputation and risk looking untrustworthy if you seem to be misrepresenting the facts to suit yourself.

DO remember three is the magic number

Some style guides recommend writing an ellipsis as three full stops: …

Some prefer three full stops with spaces between them: . . .

And some tell you to use a special ellipsis character (PC shortcut: ALT+0133, Mac shortcut: COMMAND+semicolon): …

Whichever you use (we prefer three full stops without spaces, except on Twitter), all style guides agree that an ellipsis should be three dots long: not four, not two (and five is right out). And most guides advise putting a space on either side of the three ellipsis points.

You may see what appears to be a four-dot ellipsis at the end of some sentences (eg ‘But that is not the consensus….'). This is in fact a full stop and an ellipsis – in some styles this is used to show one sentence ends and a new one begins within the omitted part of the quoted text.

When you’re using an ellipsis in the middle of a quote to show missing words, some guides recommend enclosing the ellipsis in square brackets – like this […] – to make it clear they’re not part of the quotation.

Since so many formatting matters come down to a style choice, check your organisation’s style guide (if there is one) to see which you should follow.

Now click 'Complete and continue ➜' for those all-important 'don'ts' …

Complete and Continue