Full Stop

Full Stops

Full stops are used to mark the end of sentences. Sometimes, they are used to indicate abbreviations and acronyms, or as a decimal point to separate numbers. Read about the different uses of the full stop by clicking on the tabs below.


  • Full Stop/Period
  • Full Stops with Abbreviations
  • Decimal Point

Full Stop/Period

Use a full stop (also called a period) to end sentences. Use full stops frequently. They provide structure and clarity to a text, and can help with ease of readability.

I go shopping every day.
I looked outside. It was raining again.

Use a full stop rather than a question mark to end indirect questions. (We only use a question mark if the indirect question is part of an actual question.)

I wonder what Mark is doing now.
I asked her what time she was arriving.
Can you tell me where the train station is?

Full Stops with Abbreviations

The use of full stops after abbreviations differs from American to British English. In British English full stops are not used after abbreviations, whilst in American English they usually are.

British EnglishAmerican English
Mister Mr Mr.
kilogram kg kg.
street St St.

Full stops aren’t generally used when the abbreviation is written in capital letters or when it is an acronym.

BBC (the British Broadcasting Corporation)
ATM (Automated Teller Machine)
NATO (North Atlantic Treaty Organization)

However, in American English full stops are often placed after letters to indicate abbreviations.

U.S.A. (The United States of America)
J.R. Dixon (John Russell Dixon)

If you are unsure, most common or well known abbreviations and acronyms can be found in a dictionary. Remember that consistency is important. Choose one style, and stick to it.

Decimal Point

Use a decimal point to separate dollars from cents, and whole numbers from decimals.

99.9% fat free
The average Irish family has 1.38 children.

See also: Comma: Numbers