10 Formal Synonyms for “Make Sure”

Are you trying to confirm something or want to “make sure” it happens?

Well, maybe you’re a little worried that “make sure” as a phrase is informal or unprofessional.

Don’t worry! That’s what we’re here to clear up for you.

This article has gathered some great alternatives to show you how to formally say “make sure.”

Is It Formal to Say “Make Sure”?

It is formal to say “make sure.” There’s nothing wrong with including the phrase as written in your emails when you’d like to confirm something.

It’s professional and shows you’ve thought things through. It suggests that you’ve thought about the outcomes of a situation and would like to “make sure” that things go to plan.

Of course, you can always use “ensure.” It’s a one-word variation that streamlines your writing. However, both mean the same thing.

So, we recommend reviewing this sample email to learn more about how to use it:

Dear Brian,

Can you make sure things run smoothly, please?

I trust that you’ll have a tight grasp on the team project.

Best regards,
Danielle Wolsey


  • It’s formal.
  • It’s a simple way to check something and make sure it happens.


  • It’s a bit wordy when it can easily be replaced with “ensure.”
  • It’s generic and repetitive.

“Make sure” is certainly a useful phrase in formal writing. However, it’s not the only acceptable one. So, we recommend having a few synonyms ready to go.

Keep reading to learn how to say “make sure” professionally. We’ve gathered some great synonyms and provided examples for each to teach you more about them.

What to Say Instead of “Make Sure”

  • Ensure
  • Verify
  • Confirm
  • Guarantee
  • Affirm
  • Determine
  • Establish
  • Certify
  • Check
  • Double-check

1. Ensure

You really can’t go wrong with “ensure” when looking for a formal synonym for “make sure.”

Shortening “make sure” into one word is a great way to streamline your emails.

We recommend including it when emailing an employee. It lets them know that you have something in mind for them to check on or do to ensure something takes place.

It’s also worth checking out this example before you move on:

Dear Victoria,

I would like to ensure that this runs smoothly.

So, I need you to do a few things before we can move to the next stage.

Kind regards,
Joanna Clive

2. Verify

You can also use “verify” as another way to say “make sure.” It works well in business emails when you’d like to check on something.

For instance, you can use it when emailing your boss. It shows them that you have to run something by them and would like a second opinion.

Generally, this is a great way to show you pay attention to detail. It also shows you trust and respect your boss’s knowledge more than your own.

Check out this sample email if you still need help with it:

Dear Mr. Barrowmore,

Can you verify that this is correct?

The client handed it in, but I’m unsure if the numbers line up.

Thank you so much,
Jason Reeves

3. Confirm

Feel free to include “confirm” in your emails instead of “make sure.” This is another great synonym to include that’ll help you to mix things up.

Write it when you’d like to confirm an assignment with a teacher. It shows that you’re willing to receive feedback or criticism from them, explaining whether you went wrong with something.

Generally, this is a great way to be formal and respectful with a teacher. So, you can’t go wrong with it if you’d like to get in their good books.

Here’s a great email example to help you understand more:

Dear Ms. Tyler,

Please confirm that this assignment is correct, according to your guidelines.

I’d like to get it right early before I continue to invest time into it.

All the best,
Sean Rogers

4. Guarantee

Next, we recommend using “guarantee” when you want to sound a little more confident in your writing.

You can use it when writing an email to your team of employees. It’s a great way to include everyone and show them that you have a few ideas to make sure something happens.

Emailing every employee at once allows you to be more efficient. That’s why this phrase works well. After all, it’s quite demanding and sincere. Most employees will take you seriously.

You can also review this sample email to learn more:

Dear Team,

I would like to guarantee we are on the same page with these changes.

Please reply if you have anything you’d like to share.

Melissa Carter

5. Affirm

You can use “affirm” in your academic writing to show how you’ve made sure something is correct.

It’s a great way to engage the reader and show that you’re in control of a situation.

Generally, this will work well in reports or essays. It shows that you’ve taken steps to confirm that things will take place.

The more affirmations you’ve sorted out, the more convincing your work will be to the reader.

Feel free to review these examples to learn more about it:

My boss asks me to affirm we are on the same page when running a team project. I have been given the leadership role for that reason.

I affirm most of my work is of the highest quality before handing anything in. I’m always proud of what I do.

6. Determine

Another great phrase to include in your writing is “determine.”

This time, we think you will benefit from using it in a resume. It’s a highly effective phrase that shows you go above and beyond to make sure of things.

Generally, if you “determine” that things are correct or appropriate before doing them, you’ll show the reader that you’re a hard worker.

It’s a great way to show that you take your jobs seriously and have a keen attention to detail.

You may also review these resume samples to learn more:

I always determine my work is valid and correct before handing it in. So, I have a keen attention to detail that’s worth noting.

I determine whether it is relevant to continue with work at frequent intervals. That way, I maximize my potential and productivity.

7. Establish

Next, it’s worth using “establish” instead of “make sure” to mix things up. This alternative keeps things professional and clear for readers.

Try using it when writing an essay about something that you need to verify or double-check.

It’s a great way to show that you’ve taken steps to confirm things take place. Usually, this will help the reader to see what you’re trying to say and show them that you’re in control.

We highly recommend it if the reader is a teacher or professor. It’s a great way to impress them and show them you mean business.

It may be worth reviewing these essay samples to learn more:

I like to establish things are running smoothly with every variable before moving forward. This ensures positive results.

I establish that the team is cohesive before we begin. Then, we can figure out the ground rules of what comes next.

8. Certify

Feel free to use “certify” instead of “make sure” in formal emails.

It’s an effective choice when emailing a client. This way, you can keep them in the loop about your process and show that you’re double-checking things to make sure they’re correct.

The more often you “certify” things with a client, the more confidence they’ll have in you to get the job done correctly.

You can also review this sample email to learn more:

Dear Miss Adams,

Please certify that the file I’ve sent you is the correct one.

Then, I’ll be happy to continue providing updates for you.

Harrison Bite

9. Check

There’s nothing wrong with going back to the basics in your writing sometimes.

That’s where “check” comes in. It’s a great phrase to use that shows you’re happy to check through your work.

Try using it when contacting your boss. It will show them that you’re in charge of a situation and are doing all you can to make sure things go as planned.

Feel free to review this email sample to learn more about it:

Dear Mr. Clark,

I will check things run smoothly when the time comes.

For now, please sit tight and let me respond to you at a later date.

Thank you so much,
William Howard

10. Double-Check

Finally, you can use “double-check” in formal writing. It works well when emailing employees, for the most part.

Generally, you would use it when asking employees to read through their work. It helps them to double-check a few things and ensure that no simple mistakes are made.

That way, you can guarantee high-quality work when employees hand things in.

Also, it helps you to sound bossy yet polite. Now, that’s a good combination to master when asking employees to do things for you.

Check out this email sample if you still need help with it:

Dear Brian,

Just to double-check, you have looked through your work, right?

I need to ensure there are no mistakes in it this time.

Best wishes,
Sally Anne