Parentheses: When to Use Parentheses in Writing (Examples)

If you'd like to know more about parentheses and how to use them, you've come to the right place. This article will teach you everything you need to know to use them properly and when.

In short:

• Parentheses are punctuation marks you use for adding nonessential information to your text. 

This guide is part of our free online Grammar Book.

When to Use Parentheses

So, first of all, what are parentheses? They're a pair of punctuation marks - a single one called a parenthesis - that you can use to enclose a word or group of words to separate them from the rest of the text.

In that way, they're similar to quotation marks or dashes. But the difference is that the information contained within parentheses is nonessential. In other words, removing it wouldn't affect the overall meaning, and the reader could still understand your point. 

• You'll always place a parenthesis at the beginning of the nonessential text and another one at the end, so it's wrapped up nicely like a gift.

Here's an example:

My breakfast (eggs on toast) always sustains me until lunchtime.

The reader doesn't need to know what the writer eats for breakfast. It can be helpful for them to know, but that's not the main point of the sentence. The point is to say that it sustains them until lunchtime. For that reason, leaving out the information on the specific foods eaten wouldn't affect the meaning. That's why it's in parentheses.

• Don't confuse parentheses with brackets, which are like square parentheses. They look like this: [ ].

And before we dive in and learn when to use parentheses, there's one more thing you should know:

• Parentheses can contain a single word, a sentence fragment, a complete sentence, or even multiple sentences.

Now let's get started.

Give Additional Information

The first way parentheses come in handy is to provide additional information about the rest of the sentence. Again, this information will always be nonessential but could be something you think your readers might be interested in knowing. It could be to explain or illustrate a point.

Here are some examples:

Everything I set out to do today (clean the house, fix my car and eat a nourishing meal) was a complete and utter success.

My brother (Ben) is coming for dinner. 

Tonight's gala is a huge occasion. (Everyone who's somebody will be there.)

The information within parentheses could be removed in all the examples above, and the reader would still understand what you meant.

Notice how we have a mixture of content types within the parentheses. We have a dependent clause in the first example, a single word (proper noun) in the second, and an independent clause in the third.

You can also use parentheses to clarify what an acronym stands for:

I make a monthly donation to the WWF (World Wildlife Fund).

Or to show a word can be singular or plural:

Tick the box(es) below as appropriate.

Provide the Author's Commentary

Parentheses can also be used to add your own commentary to your text as the writer. This can be a great way to bring your text alive and add some humor and personality.

Tom announced that he was leaving the company (no surprise after the events of the last few weeks).

Your submission to the contest (which caught everyone's eye by the way) has been recorded and we shall get back to you soon with the results.

Alice showed up late (surprise surprise) and was rude to everyone. Typical!

Enclose Numbers or Letters

You can use parentheses to enclose numbers or letters when you're using them to show the order in your text.

For example:

To unlock the screen, (1) press the power button, (2) swipe the screen with your finger and (3) enter your pin code.

I'm not going because (a) I don't want to, and (b) I'm too tired.

Note that it sometimes might be more appropriate to write a bulleted list, especially if there are more than four items in your list.

Cite Sources

Some style guides have you use parentheses for in-text citations. For example, the APA, Chicago, and MLA formats. This means that when you quote a journal or other reputable source in your academic paper, you must insert the author's name and year in parentheses at the end of the quote. Then, at the end of your paper, you'll have a reference list where all your citations are referenced to their broader source (this will also make use of parentheses).

Here's an example of what an in-text citation can look like:

Subjects in the study were found to be more relaxed after a warm cup of chamomile tea (Grant, 2004). 

Punctuation With Parentheses

Now that we've covered all our bases on when to use parentheses, let's see how we can make good use of punctuation in and around them. It's pretty straightforward as long as you understand a few rules.

Firstly, if the parenthetical text is a full, complete sentence that stands on its own, then you should punctuate it as usual, meaning the punctuation will be within the parentheses.

For example:

Understanding punctuation rules with parentheses is pretty simple. (But mistakes are easily made.)

Notice how the first word is capitalized, and there's a period at the end, contained within the parentheses. On the other hand, don't include any punctuation if the text contained within the parentheses isn't a complete sentence (i.e., it's a single word, phrase, or dependent clause). Punctuate the rest of the sentence as usual.

Like this:

Learn the dos and don'ts of flower arrangement (and watering) in our upcoming workshop.

Notice how the first word isn't capitalized, and there's no punctuation—only the period at the end of the sentence itself. There's one exception to this rule, and that's with exclamation points and question marks. If the parenthetical text is a question or an exclamation, you may include those punctuation marks, regardless of whether it's a complete sentence. For example:

It was then I spotted a (huge!) black spider crawling up my bedroom wall.

His dog (Rex?) was excited to see us all.

Unlike with quotation marks, commas and full stops should be placed after the closing parenthesis, as such:

I approached him (reluctatntly), and asked if he was okay.

She claimed that origami was more fun than Twister (but I'm not sure she really believed it). 

Some Additional Notes on Parentheses

We've covered most of what you need to know, but I want to address a few more points before I conclude this article.

Read on to find out what they are.

Subject-Verb Agreement

One of the most important things you'll ever learn - a rule that spans the entire grammar spectrum - is always ensuring subject-verb agreement.

• Subject-verb agreement is when the verb is conjugated correctly according to its subject.

For example, the following sentence does not have correct subject-verb agreement because the subject is 'boys,' which is third person plural, and the verb is 'loves,' which is the conjugation for third person singular only.

The boys loves spaghetti bolognese for dinner. 

For this sentence to have correct subject-verb agreement, we'd have to change the verb to 'love.'

Applying this to sentences with parentheses can be a little tricky because you must ignore the text within the parentheses.

For example:

My mum (and half the population) loves the new Elvis movie. 

At first glance, it might appear that this sentence doesn't have correct subject-verb agreement because 'mum' + 'half the population' = a plural subject. But this isn't the case since we must ignore the text within the parenthetical phrase ('half the population') and count only 'mum' as the subject. Therefore, the subject is singular, and 'loves' is appropriate.

Here are some more examples:

Tom (along with the rest of us) was very disappointed with the outcome.

My daughter (and her cute pup) is joining us later.

The country (and to some extend, the whole continent) is in crisis.

Use Parentheses Sparingly

Last but not least, use parentheses sparingly. This punctuation mark is often overused, which causes it to lose its effect. To avoid this, ensure you only use it when the information contained within it is something you'd be happy to remove. Look at your sentence and ask yourself, would the sentence still make sense without this information? If so, then you can put it in parentheses. If not, then don't.

Also, ask yourself whether a different punctuation mark would be better suited. Try dashes, for instance, or even commas, and see if that works better. Sometimes, more than one option is appropriate, so it's up to you to pick the best one.

Case in point:

My sister (whom I love dearly but who annoys me greatly) always steals all my clothes.
My sister, whom I love dearly but who annoys me greatly, always steals all my clothes.
My sister - whom I love dearly but who annoys me greatly - always steals all my clothes.

Concluding Thoughts

That concludes this article on parentheses; I hope you found it helpful and feel that you understand how and when to use them.

Let's summarize what we've learned:

• Parentheses are a form of punctuation.
• You can use them to provide additional, nonessential information or extra commentary, cite sources, or enclose letters or numbers in lists.
• Watch out for your punctuation in and around parentheses.
• Ignore the parenthetical text when checking subject-verb agreement.
• Use parentheses sparingly.

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