Writing numbers

Large numbers should be read in groups of hundreds. Note that after a number, hundred, thousand, million and billion have no –s.

  • Two hundred (NOT Two hundreds)
  • He is worth ten billion. (NOT He is worth ten billions.)

If there is no number before these words, we usually use their plural forms. Of is also used.

  • He is worth billions of dollars.

In British English, we use and before the tens in a number.

  • 240 – Two hundred and forty

In American English, and can be dropped.

  • 350 – Three hundred and fifty OR Three hundred fifty
  • 6,374 – Six thousand three hundred and seventy four

In writing, large numbers are usually divided into groups of three with commas. Note that full stops are not used in this way.

  • 5,385 (NOT 53,85) (NOT 5.385)

Commas are not used in years and they can be left out in four-digit numbers.

  • She was born in 1972. (NOT She was born in 1,972.)
  • 3874 OR 3,874

We can say a hundred or one hundred, a thousand or one thousand.

  • Few people manage to live for a hundred years.
  • You have to give me one thousand dollars.

Billion and million

A million is a thousand thousand. It has got 6 zeroes. In American English, a billion is a thousand million. In British English, too, a billion is now a thousand million. However, in British English, a billion used to be a million million.