Full Stops (Periods) in Abbreviations (Grammar Lesson)
The Quick AnswerAbbreviations can be written with or without periods () full stops (). Often, you have a choice. In other words, you can write:
- C.N.N. or CNN
- e.g. or eg
If the abbreviation is a proper noun (e.g., a company name), copy the official version.
This guidance does not apply to titles such as Mrs., Mr., Ms., Dr., Prof., Capt., Gen., Sen., Rev., Hon., and St.
Read about using periods / full stops in titles.
Periods (Full Stops) in AbbreviationsIt is considered untidy to mix abbreviations with periods and ones without periods in the same article. These two examples have been marked as correct because the writer has been consistent.
- The band travelled around UK and USA last year.
- The band travelled around U.K. and U.S.A. last year.
- It was only shown on ITV and not B.B.C. (This is an inconsistent use of full stops (periods). It is considered untidy.)
- The M.D. insisted that his PA had left by 4 o'clock. (Untidy)
The Tendency: Use Periods Only in Uppercase AbbreviationsAbbreviations made up of capital letters tend not to have periods, but abbreviations made up of lowercase letters tend to have them. For example:
- BBC (British Broadcasting Corporation)
- LRS (Linear Recursive Sequence)
- CBS (Columbia Broadcasting System)
- a.m. (ante meridiem - before midday)
- p.m. (post meridiem - after midday)
- i.e. (id est - that is)
- e.g. (exempli gratia - for the sake of an example)
- p.p. (per procurationem - by the agency of)
If the abbreviation is a proper noun (e.g., a company name), copy the official version. For example:
- Our team was hosted by the Italian club A.S. Livorno Calcio. ("A.S. Livorno Calcio" (with periods) is the name shown on the logo and in all correspondence.)
- The shop will be taken over by the clothing company s.Oliver in June. ("s.Oliver" is the official version.)
- We will meet at P.F. Chang's in Tokyo. ("P.F. Chang" is the official version.)
Do Not Use Two Periods If Your Sentence Ends with an AbbreviationIf your sentence ends with an abbreviation (including a contraction like "etc.") that ends with a period, do not use a second period to show the end of the sentence. However, other end marks (such as question marks, exclamation marks) should be used. For example:
- I need milk, bread, cheese, etc.
- She moved from I.T.V. after an irresistible offer from the B.B.C.
- She moved from I.T.V. after an irresistible offer from the B.B.C.. (Logically, this is correct, but it is too unwieldy.)
- Will she move back to the B.B.C.? (This is correct, but it looks a little scruffy. To avoid this, use BBC instead of B.B.C.)
- Standing tall and with the Lord's Prayer mumbling across our lips, we entered the chamber...." (This ends in four dots: three for the ellipsis and one to end the sentence.)
"In Other Words" or "For Example"?The abbreviation "i.e." (id est) means "in other words" or "that is to say." The abbreviation "e.g." (exempli gratia) means "for example." Do not confuse the two.
- It happened in August, i.e., two months ago.
- All amphibians are thriving in the new pond; e.g., two bullfrogs were spotted yesterday.
- They all passed easily, i.e., Jane scored 80%.
Etc. Etc.The abbreviation "etc." is a contraction of et cetera. However, it is often mistakenly written as "ect." (This is because many people pronounce it "eccetra.")
- For a small monthly bonus, you can present staff with shop tokens, flowers, chocolates, theatre tickets, ect. (It is normal to include the period with "etc.")
Finish the AbbreviationIf using periods in abbreviations, ensure you give the last letter a period too.
This garage sign in the UK should say "M.O.T."