When do I use assure?

Updated 2026-07-10

Insure vs. Ensure vs. Assure

Insure = insurance. Ensure = make certain. Assure = reassure a person.

Insure relates to insurance: "Insure your car before driving."

Ensure means to make certain: "Ensure the door is locked."

Assure means to reassure someone: "I assure you, it's fine."

In American English, insure and ensure are sometimes used interchangeably for "make certain," but careful writers keep them separate.

Ensure your car before driving.

Insure your car before driving.

I assured the door was locked.

I ensured the door was locked.

When reassuring a person: "I assure you, the data is accurate."

Last updated: 2026-07-10