When to use & instead of “and”

Question

Are there rules of usage when using the ampersand "&" instead of "and"?

Are they completely interchangeable?

The ampersand seems more casual, but I'm not sure.

Answer 1

There are very, very few acceptable uses of & in proper written English. Here are some of them:

& is especially common when joining names to indicate a firm or a partnership, for example, a law firm:

 Baker & McKenzie
 Abercrombie & Fitch
 Crosby Stills Nash & Young

In abbreviations, when abbreviating "and", & is often used:

 AT&T (American Telephone and Telegraph)
 P&L (profit and loss)
 R&D (research and development)

One rare usage is on envelopes addressed to a couple:

 Mr. & Mrs. Jackson

&c. is a rare and somewhat archaic looking abbreviation for etc.

Other than that it is vanishingly rare to see & in formal written English, although of course in informal email, text messages, notes, and handwriting, anything goes.

Answer 2

Are there rules of usage when using the ampersand "&" instead of "and"?

I looked through a couple of reference books and both of them said that the ampersand should only be used in company names.

Are they completely interchangeable?

Meaning-wise I think they are.

The ampersand seems more casual, but I'm not sure.

It's an abbreviation so one might use it more in less formal writing.

Answer 3

I cannot say this is correct but in use I find it very useful....

I often use "&" when two things are related directly but only in a series... example: Michel has experience in Marketing, Research & Design, and Business Management....

like I said, this most likely isn't correct but it makes sense, seems useful, and if enough people agree then we can change the rules & regulations.