JS Tip 82: From the Writing Workshops: “Ensure,” “Assure,” and “Insure”

Sarah Enders asks, “What’s the difference between ‘ensure’ and ‘assure’?”

We’ll go one better and throw “insure” into the discussion.

As with many words, the differences are not absolute and grow murkier when we deal with our British counterparts.

Generally—

•   Ensure means “to make certain” or “to guarantee.” “My job is to ensure my Uncle Fred drinks his Ensure.” (“My job is to make certain my Uncle Fred drinks his Ensure.”)

Some UK usages and some rare US usages allow you to use “ensure” and “insure” interchangeably. We think that’s a bad idea; it’s too confusing.

•   Assure means “to promise” or “to convince.” “I assure you the check’s in the mail.” (“I promise you the check’s in the mail.”)

•   Insure means to secure financial coverage. “I need to insure the ‘66 Mustang.” (“I need to provide financial coverage for the ’66 Mustang.”)

A good way to remember the specific use for ‘insure’ is to think of the “i” as the crossbar on the dollar sign: “I need to $nsure the Mustang.” “Insure” and “insurance” are always dollar-related.

Test Yourself

a.  “In real life, I _______ you, there’s no such thing as algebra.” (Fran Lebowitz)  

b.  “The FDA’s job is to _______ the safety of the drug supply.”

c.  “He tried to _______ his car, boat, his motorcycle, and his dog.”

If you have questions or comments, let us know. As we’ve said before, we love this stuff.

The Answers

a.  “In real life, I assure you, there’s no such thing as algebra.” (Fran Lebowitz)

b.  “The FDA’s job is to ensure the safety of the drug supply.”

c.  “He tried to insure his car, boat, his motorcycle, and his dog.”