Difference between insure and ensure
This is the third part of the difference between series.
Having worked in a university for over 6 years, I’ve been exposed to a lot of academic writing. The only thing worse than academic writing is business writing. Considering I work in a faculty of management, I get to see the worst of both worlds. Apparently, there isn’t much in the way of grammar instruction in order to get a PhD.
Anyhow.
A common mistake I see in writing is the confusion of “insure” and “ensure”. For example:
Please insure everyone is invited to the meeting.
Never mind the wordiness and the passive voice, this sentence is saying something different from what was intended.
The speaker wants to make sure that everyone knows about an upcoming meeting. Unfortunately, using the word insure implies that the person to whom the command is given is to take out an insurance policy regarding the invitations.
That is what it really comes down to. “Insure” means to issue an insurance policy. The following is what the person should have said.
Please ensure everyone is invited to the meeting.
Some may disagree with this stance and claim the two terms are interchangeable, but I’m not willing to accept that quite yet. I am a proponent of clear, unambiguous sentences. By separating these two meanings, we encourage people to clearly say what they mean.
Let me know if you have any grammar questions, and I’ll be sure to post the question and answer here.


Basically, insure, ensure, and assure mean to make a person or thing more sure. Insure should be restricted to providing or obtaining insurance to indemnify or guarantee someone or something against a loss. Ensure can be used in all other senses, especially ‘to make certain’. Ensure can also imply a guarantee. Then there is a third word, assure, which means to make a promise or convince. Assure also implies the removal of doubt and suspense within someone’s mind. Here are some examples of usage for assure, ensure, and insure: I assured him that I would not clean out his tool and hardware collection. She looked back to assure that no dogs were following her. / The government ensured the safety of the troops during the time they would be airlifted out of the country. We will ensure that the abusive coach will not return next year. / She was insured against loss in the homeowner’s policy. The valuables are insured.
Comment by Amit Verma — 30 Jan 08 @ 21:40
And for those who are sticklers for citing sources, Amit’s comment was entirely lifted from Dictionary.com.
Comment by Kim Siever — 31 Jan 08 @ 5:41
When you profess to know grammar and complain about the incorrect usage of words, how about following the rules yourself? I thought we were all taught that sentences begin with capital letters (see first paragraph of the post). Not to mention the fact that “Anyhow” by itself is not a sentence.
Comment by Dan McKenna — 3 Nov 08 @ 15:08
I was reading this while drinking my Ensure and thought there was a bunch of effort put into all this.
Comment by Craig — 4 Nov 08 @ 12:47
Please tell me how to use lay, laid, lain, lie, etc., in a way the I can remember it. Thx!
Comment by Becky Beachan — 11 Nov 08 @ 11:06