Ensure and insure each describes the act of making sure something will happen, although insure is used in the context of an insurance policy. The word ensure is used for any subject and is typically the most appropriate word to use.
Your writing, at its best
Compose bold, clear, mistake-free writing with Grammarly's AI-powered writing assistant
Insure and ensure are very similar words and used often enough to think they are used synonymously. While both words carry the meaning of guaranteeing somebody of something, the correct usage of insure and ensure is dependent on the subject context.
In general, the word ensure is defined as the act of making sure something happens, while insure is the act of providing payment in the event of an accident. Insure is rarely used in place of ensure for formal writing, and it is best only to use insure while discussing insurance-related topics, such as insurance policies or insurance companies.
Why insure and ensure are commonly confused words
English speakers use the words insure and ensure so often that it’s not easy to tell the difference between them. Here are a few reasons the word duo is easily obscured.
The faux-synonymy between insure and ensure is clear if we notice how advertisements use them interchangeably as a clever pun, such as insurance companies with names like Esurance. Another popular insurance company’s advertising motto states, “You’re in good hands,” which eludes to the definitions of ensure and assure. All three words are very similar conceptually, but each word carries a different meaning.
Insure and ensure sound the same
A second reason insure and ensure are commonly confused words is because they are homophones, which are sets of words that are spelled differently but sound the same. Insure and ensure are not proper homophones in the United Kingdom, though, because British pronunciations tend to enunciate vowels completely.
Assure vs. ensure vs. insure
As if the English language couldn’t make communication any more complicated, there remains one word to confuse them all: assure. Each of these words is similar in meaning because they all serve the function of making someone or something feel sure or certain.
The word assure does what insure and ensure attempt to do, which is the act of guaranteeing an outcome with positive affirmation and confidence. To assure somebody is to cheer, comfort, console, or soothe them, which isn’t to say that it’s impossible for the words insure and ensure to have the same effect, but the act of assuring another person is a convincing one and allows someone to feel safe and certain.
Assure derives from the Latin terms ad– (to) and Securus (secure), which eventually developed into the late Middle English term we use today. Synonyms for assure include insure and ensure but assure also encompasses the meanings for empathy, sympathy, and relief.
Grammar tips for using assure vs. ensure vs. insure
The uncertainty about using insure or ensure is resolved with one simple question: are you talking about an insurance policy? If so, insure is the correct word to use, but in all other cases, ensure is the safest way to go.
If you are stuck between using ensure or assure, ask yourself: Am I certain of my message’s accuracy, and will it provide comfort to another person? If so, then use assure, but if not, stick with ensure.
How to use assure vs. ensure vs. insure in a sentence
Understanding the difference between assure, ensure, and insure is easier when viewing them side-by-side. Let’s take a look at how each word is used within their direct definitions:
I can assure you that you are beautiful just the way you are. My professor assured me that she would send letters of recommendation to my top three universities. I heard the mother assuring that there would be ice cream at home.
Can you ensure that your homework will be turned in on time? The mother ensured there would be ice cream ready for her family. We spent the weekend ensuring we were ready for the camping trip.
Our insurance policy will insure my home up to $500,000 in the event of a house fire. My car is insured. My dad is insuring my car through his company policy.
What does ensure mean?
The definition of ensure is to promise or guarantee something will happen. Ensure is a verb, so it is an act of stating one’s intentions of following through on something they committed to or carry out a favor that has been asked of them.
Synonyms of ensure
The English language uses idioms that are similar to ensure like “(as) clear as day,” or phrases such as, “you have my word.” Additional synonyms of ensure include:
Assure, establish, insure, protect, provide, guard, secure, and safeguard.
What does insure mean?
The word insure is a transitive verb defined as the action of providing or obtaining an insurance policy through an insurance company. Insure has a similar secondary meaning, which is the act of taking necessary precautions in the event of uncertainty, although it is uncommon to use outside of the context of using insurance.
An insurance policy is a contract made between a consumer and an insurance company where, over an extended period, you agree to pay a certain amount of money to said company. If a costly event occurs during that time, such as a medical treatment, natural disaster, or a car accident, the insurance provider will cover the majority of your bills up to an agreed-upon amount. An insurance policy also dictates what a provider will cover, so it’s important to read the fine print.
There are many reasons people buy insurance that doesn’t have to involve crises, either. In fact, it’s illegal not to have car insurance in most US states, and it’s required for citizens to purchase a form of health insurance for their typical health needs, such as visiting a primary care doctor or visiting the dentist. Insurance is also crucial for protecting you from people who are trying to take advantage of you, such as faking an injury to pay for nonexistent medical bills, or auto-theft and burglaries.
People also buy insurance for their homes, rental units, pets, savings accounts, luxury items –– such as jewelry or art –– and, finally, people buy insurance for their own life. That’s right– people purchase life insurance to prepare for death so that their loved ones won’t suffer the costs associated with losing them. This makes more sense when we think about how losing a home provider, or a costly funeral can impact our loved ones. The point is, an insurance policy helps protect people from going broke when living becomes too expensive to pay out-of-pocket.
Test your ensure vs. insure grammar skills with the following multiple choice questions:
The New York Times ensures transparency in their news coverage.
Ensures and assures
Using flashcards helps assure students they will receive a good grade.
Ensure and assure
Policy-holders of this type of insurance assure security for their loved ones after they die.
None of the above
My friend’s constant assuring helped me overcome my insecurities.
Assurance or assuring
Publishing stylebooks ensure correct spelling and grammar.
The Word Counter is a dynamic online tool used for counting words, characters, sentences, paragraphs, and pages in real time, along with spelling and grammar checking.
Alanna Madden is an online content editor and freelance writer based out of Portland and Eugene, Oregon. She has over three years of professional experience involving arts, culture, and news editing, and currently specializes in data reporting on US higher education. Alanna graduated from Portland State University with a Bachelor of Science in English with a writing minor. In addition to literary studies, she spent several years studying molecular biology and volunteering as a research assistant at Oregon Heath and Sciences University. Outside of work, Alanna enjoys reading and writing about literary criticism and participates in local writing groups. I can be found on Linkedin .