The ways to incorrectly write big numerals in copy seem infinite. But with these simple AP Style rules, you’ll establish consistency and put your readers at ease. 

With millions, billions and trillions, always use figures except in a casual reference:

  • Correct: I just won a million dollars!
  • Correct: The capital campaign will top $1 billion by 2024.
  • Incorrect: The hurricane caused $1,000,000,000,000.00 worth of damage.

Don’t go beyond two decimal places:

  • Correct: Phoenix’s population is estimated to be 1.63 million.

Do not leave out million, billion or trillion with a range of figures: 

  • Correct: A donor has indicated she will make a gift in the range of $20 million to $30 million. 
  • Incorrect: The malpractice lawsuit is estimated to cost the hospital between $3 and $9 million.

—Sarah Muench