Grammar Slammer – Insure, Assure and Ensure

As a writer, I frequently run into words that raise a question mark above my own head.

Today, while writing the conundrum of “insure”, “assure” and “ensure” came up. So I thought for my fellow writers (and anyone else that might find it helpful), I would clarify these three frequently confused words:

Assure vs. Ensure vs. Insure

All three words share an element of “making an outcome sure.” However, rather than using these words interchangeably, let me point out the unique aspects of each word so that you can use them to communicate your intention clearly.

Assure is to promise or say with confidence. It is more about saying than doing.
Example: I can assure you that I do know the answer.

Ensure is to do or have what is necessary for success.
Example: Using spell check will ensure that your words are spelled correctly.

Insure is to cover with an insurance policy.
Example: I need to insure my car with a new line of coverage.

Especially in American English, what you insure is a business transaction. What you ensure results from your personal efforts. What you assure is a statement of confidence.

I hope that helps!