Assure, Ensure, or Insure?

by Craig Shrives

The difference between "Assure," "Ensure," and "Insure"

"Assure," "ensure," and "insure" are easy to confuse because they sound so similar.
  • "Assure" means to promise or to say with confidence.
    • I assure you that I will not be late. correct tick
  • "Ensure" is to make certain that something will happen.
    • Keep stirring the fudge to ensure it does not set. correct tick
  • "Insure" is to arrange for compensation in the event of damage, loss, injury, or death.
    • It is hard to insure my house since the hurricane. correct tick
assure, ensure, or insure?

Assure, Ensure, and Insure

Confusion with "assure," "ensure," and "insure" most commonly occurs with the following terms.

Common terms with "assure":

  • To assure a loved one
  • To assure a customer

Common terms with "ensure":

  • To ensure success
  • To ensure compliance
  • To ensure freedom
  • To ensure job security

Common terms with "insure":

  • To insure a car
  • To insure a phone
  • To insure a building


The verb "to assure" means to state with confidence. (NB: The noun "assurance" means a belief in ability.)

Example sentences with "assure":
  • Do not worry about your difficulties in Mathematics. I can assure you mine are still greater. correct tick (Physicist Albert Einstein)
  • Students rarely disappoint teachers who assure them in advance that they are doomed to failure. correct tick (Philosopher Sidney Hook)


The verb "to ensure" means to make sure something will happen (i.e, to guarantee).

Example sentences with "ensure":
  • Voting is the most precious right of every citizen, and we have a moral obligation to ensure the integrity of our voting process. correct tick (Politician Hillary Clinton)
  • Good wishes alone will not ensure peace. correct tick (Chemist Alfred Nobel)


The verb "to insure" means to issue an insurance policy to provide compensation in the event of theft, loss, damage, or death.

Example sentences with "insure":
  • I own stock, and I also insure my car with Geico. correct tick (Baseball player Ernie Banks)
  • Nearly half of American seniors were forced to go without coverage because insurance companies were reluctant to insure them. correct tick (Politician John B Larson)

Ready for the Test?

Help Us Improve Grammar Monster

  • Do you disagree with something on this page?
  • Did you spot a typo?

Find Us Quicker!

  • When using a search engine (e.g., Google, Bing), you will find Grammar Monster quicker if you add #gm to your search term.