Fishes or Fish’s or Fishes’? (Correct Possessive Explained)

The possessive form can be a tricky thing to figure out. Luckily, this article will aim to help you understand the most obvious things that you need to focus on. We’ll look at “fish” and how the possessive forms work in both the plural and singular cases.

Fishes or Fish’s or Fishes’: Which Is The Correct Possessive Form?

“Fish’s” is the singular possessive and plural possessive of “fish.” We can use “fish” as both the singular and the plural form, and it’s the most common way to use it in English. However, some people prefer using “fishes” as the plural form, allowing “fishes'” to be the correct possessive.

Fishes or Fish's or Fishes': Which Is The Correct Possessive Form?

“Fish” is one of those words that doesn’t follow all the standard forms we might expect. After all, it has the same spelling in both singular and plural forms.

Some people get confused by this because it means we have to focus on special possessive rules that aren’t there with other nouns.

Here are the main forms:

Singular possessiveFish / Fishes
Plural possessiveFish’s / Fishes’

As you can tell, the singular possessive form is definitely the easiest one to use. There is only one form that we need to worry about. “Fish” is the same no matter how we use it in the singular form.

To turn “fish” into the singular possessive form, we simply add an “‘s” to the end of the word. This is the easiest way for us to show that a “fish” owns an object, and there’s only ever one “fish” referred to in this way.

The plural possessive form is the tricky one, and we’ll spend a lot of time making sure we’ve got it right. Both “fish’s” and “fishes'” are correct as the plural possessive form for “fish.” We add an “‘s” to the end when it’s using the plural form “fish,” but we drop the “S” when we use the form “fishes.”

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The most basic form to go through is “fishes.” This is one of the two options we have for the plural of “fish.”

“Fishes” is uncommon, though it is correct as the plural for “fish.” We can use it when we’re talking about more than one “fish” in a sentence.

The plural form for “fish” is both “fish” and “fishes,” which is where a lot of people’s issues lie with the possessive forms. Luckily, we’re only worried about “fishes” in this section, so we’ll focus our examples on that.

  1. Plenty of fishes has been found swimming in these waters.
  2. I like a lot of fishes, so I’m not able to pick out my favorite.
  3. These fishes aren’t particularly popular.
  4. Many fishes make my father a happy man after a long day out on his boat.
  5. The fishes in these waters aren’t nearly as edible as those ones!

“Fishes” is an uncommon plural form for “fish.” It’s much more common to use “fish,” but it’s still a valid example.


“Fish’s” is both the singular and plural possessive form of “fish.” It’s not all that confusing once you understand what we mean by that.

“Fish’s” can be the singular possessive form when we take the singular form “fish” and add an “‘s” to the end. It can also be the plural possessive form when taking the plural form “fish” and adding an “‘s” to it.

“Fish’s” can refer to one “fish” owning an object in a sentence. This is how the singular possessive form works and is how we can use it to show ownership.

However, “fish’s” can also refer to more than one “fish” owning an object or group of similar objects. This would make it the plural possessive form, which is a little less common but still something you need to know how to use.

To create the possessive form in either case, we add an “‘s” to the end. This is a common and expected rule, which helps us when it comes to explaining it.

  • Singular: The fish’s family is somewhere around these parts.
  • Plural: Those fish’s eyes aren’t looking as good as they should do.
  • Singular: The fish’s fin is a bit wobbly.
  • Plural: The fish’s habitat is slowly being destroyed.
  • Singular: The fish’s swimming pattern needs refining.
  • Plural: Those fish’s food sources are fallen to pieces when they hit the water!

“Fish’s” works as both the singular or plural possessive forms. The rules are fairly standard for both of them; it’s only the amount of “fish” that changes.


“Fishes'” uses the uncommon plural form “fishes” as its root word. This makes it an uncommon possessive form in itself, and it’s not likely you’ll ever find anyone using this.

While uncommon, “fishes'” is still correct. We use it only as the plural possessive form. It works to talk about multiple “fishes” owning an object or group of similar objects in a sentence.

This time, we drop the “S” after the word because the word “fishes” already ends with an “S.” This is common practice for a lot of plural possessive forms.

  1. The fishes’ families are all migrating somewhere north.
  2. These fishes’ needs far outweigh the needs of the ducks in this area.
  3. Those fishes’ swimming patterns are all messed up.
  4. Both of the fishes’ tails need correcting.
  5. Many fishes’ habitats are slowly being ruined by people.

Quiz: Have You Mastered Fishes or Fish’s or Fishes’?

Finally, let’s see how you fare with a quick quiz.

  1. That (A. fishes / B. fish’s / C. fishes’) scales are magnificent.
  2. Many (A. fishes / B. fish’s / C. fishes’) ponds are being renovated in this area.
  3. The (A. fishes / B. fish’s / C. fishes’) have gathered together in the corner.
  4. This (A. fishes / B. fish’s / C. fishes’) timing is amazing.
  5. Your (A. fishes / B. fish’s / C. fishes’) eyes are wonky.

Quiz answers

  1. B
  2. B or C
  3. A
  4. B
  5. B or C

Final Thoughts

“Fish” is the singular and plural form. Therefore, we can use “fish’s” as the correct singular and possessive plural form. “Fish’s” is the most common form, and it’s not common to see “fishes'” used alongside it. Still, they’re both valid options, and it’s up to you which you prefer.

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