Punctuation in abbreviations

The Oxford Dictionaries website offers clear and succinct guidelines re punctuation in abbreviations – see below. The wording (e.g. "you don’t need to") would suggest that, as is often the case for English, these are indeed 'just' guidelines, rather than the more prescriptive rules for German, for example.

People are often uncertain about whether or not to use full stops in abbreviations. Here are some guidelines:

1. In both British and American English, if you are using initial (i.e. first) letters to represent words, you don’t normally need to put a full stop after them:

BBC

UK

NATO

2. In American English, however, it is common to use a full stop as an alternative style for certain abbreviations, in particular:

USA or U.S.A.

US or U.S.

3. If an abbreviation consists of the first and last letters of a word, you don’t need to use a full stop at the end:

Mr

Ltd

Dr

4. If the abbreviation consists only of the first part of a word, then you should put a full stop at the end:

Wed. [= Wednesday]

Dec. [= December]

See more information about abbreviations.
Back to punctuation.
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