Making Words Possessive Using the Apostrophe "S" Rule

The possessive form is the way we indicate ownership. By adding either an ‘s (apostrophe + “s”) or an apostrophe on its own, we indicate that something is owned by a person, animal, place, or organization.

What Is the Apostrophe “S” Rule?

The rule above is simple enough, but as usual with the English language, the devil is in the detail. Although it is easy to form a possessive with singular nouns and regular plural nouns, the moment you throw in words ending in s, things get more confusing.

There are two main reasons for such confusion. The first is that the hissing (sibilant) sound of more than one s makes people question their grammar choices when it comes to apostrophes. The second is that when it comes to possessives of words ending in s , there is no single right answer—different stylebooks offer different guidelines!

Thankfully, as this article will show, the fixed rules on the possessive form of words ending in s are easy to remember and the rest of the time it’s just a matter of preference and consistency.

Forming the Possessive: Singular Nouns

The ‘s is added to singular nouns (people, places, animals, organisations, countries, etc.) to show possession. Examples include:

The child’s teddy bear	Andy’s bike
England’s national team	London’s cinemas
The flower’s petals	Nina’s sweets
The lawyer’s generosity	Roger’s dog

As can be seen from these examples, the possessive indicates not just ownership, but also relationships, characteristics, and other indicators of belonging. For example, the possessive form can indicate where someone works or studies:

• Adam’s school
• Jenny’s office

It can also show ownership of mood or behavior:

Petra’s patience was wearing thin in the face of John’s buffoonery.

And it occurs in less obvious fixed phrases:

• At death’s door
• An honest day’s pay

On the other hand, the ‘s is not used to show possession when it comes to things such as objects, furniture, or houses. So, rather than talking about the door’s handle, we say the door handle. Similarly:

• Hotel lobby, not hotel’s lobby
• Dining room table, not dining room’s table

How to Make Words Ending in “S” Possessive

Okay, so far, so simple, but what about if the singular noun ends in s already? As we have just seen, a singular noun adds an ‘s to show possession. But it's when that singular noun already has an s at the end that people get confused. The rule, however, is still to use ‘s to show possession:

• The bus’s windows
• The abacus’s red beads
• The boss’s affairs

How Is the Possessive Form of a Name Ending in “S” Written?

Things get a little more interesting with names that end in an s. There are two ways of doing things, depending on your own preference or which stylebook you are using. The most common approach is to still use the ‘s as you can see below:

• Jess’s cricket bat
• Chris’s lunchbox
• James’s favorite pencil
• Yeats’s poems about Ireland

This is what most style guides suggest, including The New York Times, the BBC, MLA, and The Economist. However, there are several institutions that disagree, including the Associated Press, and they opt for an apostrophe alone. The above examples would therefore be written like this:

• Jess’ cricket bat
• Chris’ lunchbox
• James’ favorite pencil
• Yeats’ poems about Ireland

Is It Chris’ or Chris’s?

Which way should you go? Rather than follow a specific stylebook, it is perhaps best to simply allow form to follow function. Ask yourself how it sounds when you are speaking? If you would say Chris -iz cat,—which most people would—then it makes sense to write Chris’s cat.

Is It James’ or James’s?

Again, writing as if you were speaking the sentence, the extra ‘s should probably be added. It is preferable to write James’s favorite pencil because you would say James iz pencil. But remember, neither option is technically wrong.

When Do You Not Use Apostrophe “S” After Names?

Equally, there will be cases where it makes no sense to use the ‘s because you wouldn’t say it like that when speaking. For example, Tim Robbins’ driveway is preferable to Tim Robbins’s driveway because saying Tim Robbins -iz driveway is too much of a mouthful. Similarly:

• Kenny Rogers’ new album
• Socrates’ trial
• Archimedes’ principle

Classical Names and the Possessive

This brings us nicely to another commonly accepted guideline—that biblical or classical names ending in an s all drop the ‘s. Thus:

• Jesus’ disciples
• Moses’ sermons
• Achilles’ heel

What About Proper Nouns Already in the Possessive?

Occasionally you will come across a proper noun that already takes the possessive form. For simplicity this should be left as is:

• McDonald’s new vegan menu
• Sainsbury’s plastic bag policy

When There Are Two Possessive Nouns in a Sentence, Is Apostrophe “S” Added to Both?

With joint possession and a list of names, we add the ‘s to the last name. For example:

President Obama and President Trump’s book on bridging the divide in America.

In this (unlikely) instance the two presidents would have co-authored a book. Similarly, if two people share possession of an item or person:

• Jack and Jill’s house
• Peter and Paul’s father

However, if Jack and Jill had separate houses, it would be written as:

Many of these houses, including Jack’s and Jill’s, were built in the 1900s.

Singular Nouns in Plural Form

Lastly, for the few singular nouns that are already plural words, the rule is to simply add an apostrophe. Thus:

• Abbey Road is the Beatles’ finest album.
• La Fourchette is Beverly Hills’ best restaurant.

There are a lot of rules to take in here but most of the time it’s just a case of saying the word in your head before writing it.

If you start doubting your own head (which we all do from time to time) run your work through a grammar checker such as the ProWritingAid Grammar Report. This will flag any inaccuracies and suggest the best option. With ProWritingAid you can even set your own house style to maintain consistency when forming those trickier possessives.

Forming the Possessive: Plural Nouns

Thankfully, in comparison with the complicated variations of singular noun possessives, plural noun possessives are quite straightforward.

Regular Plural Noun Possessives Do Not Use Apostrophe “S”

The basic rule is that when it comes to regular plural nouns, we do not use ‘s. A plural noun that already ends in an s takes only an apostrophe:

• My parents’ vinyl collection
• The Daleks’ inability to navigate stairs
• The boys’ treehouse
• The players’ changing rooms

Keeping Up with the Joneses

This rule also applies to names that are plural:

• The Joneses’ front garden looks like a tip.
• The Jeffersons’ summer parties are unmissable.

Irregular Plural Nouns Use Apostrophe “S”

However, for irregular plural nouns—those that don’t end in s—we use the ordinary possessive form:

• Children’s books
• The media’s complicity
• Women’s rights

How to Handle Apostrophes in Unusual Situations

In addition to the exceptions for singular and plural nouns mentioned above, there are a few other situations that merit attention.

Possessive Apostrophes in Place Names

Once again, we come to differing guidelines, this time dependent on location. In the US, most place names don’t bother with a possessive apostrophe regardless of whether they end in s or not:

• Kings Island
• Pikes Peak
• Whites Creek
• Harpers Ferry

There are surprisingly only five exceptions to this rule in the whole of the US:

• Martha’s Vineyard
• Ike’s Point
• John E’s Pond
• Carlos Elmer’s Joshua View
• Clark’s Mountain

However, in the UK all hell breaks loose, grammatically speaking! The rules are, there are no rules, so you get:

• Bishop’s Stortford
• Bishop’s Castle
• Earl’s Court
• St James’s Park

But then you also get:

• St Albans
• St Helens
• Barons Court
• St James Park
• St James’ Park

There’s not much that can be done about this and in the end it’s just a case of learning the historical quirks of a particular place!

Possessive ’S and Indefinite Pronouns

Indefinite pronouns such as somebody, anybody, anyone, or one all take the possessive ‘s:

• It is important to be confident of one’s fighting skills before entering the ring.
• Is this someone’s Harry Potter scarf?

Possessive ‘S and Possessive Pronouns

On the other hand, you should never, ever use an ‘s with possessive pronouns.

This means you should write:

Is that car yours? rather than Is that car your’s?

This issue crops up most often with the pronoun its, which should always be written without the apostrophe in the possessive:

The car needed its oil changed.

It’s Okay for Possessives to Drop Their Noun

There are some situations where it makes perfect sense to drop the noun that the possessive apostrophe relates to:

• We went to Andy’s after the pub closed. (referring to Andy’s house)
• I bumped into Julie at the hairdresser’s. (referring to the hairdresser’s salon)

Short Answers Can Also Drop the Noun

Similarly, it is also acceptable to drop the full noun phrase and use the possessive alone to avoid repetition:

• Is that your walking stick?
• No, it’s Harold’s.

For Goodness’ Sake!

Lastly, most style guides suggest that an apostrophe is used on its own, without the s, when sake follows the noun:

• For goodness’ sake
• For convenience’ sake
• For appearance’ sake

However, once again there are some stylebooks (for example, the Chicago Manual of Style) that say that if the word before sake doesn’t end in an s then it should get the ‘s:

• For appearance’s sake
• For convenience’s sake

As with all the examples in this article, if there is no fixed rule, the best way to go is to write it as you would say it.

What Is the Possessive Form of Words Ending in “S”?

In summary then, the basic rules on the possessive form of words ending in s are simple and leave little wriggle room. For words like bus, abacus, crocus you still add the ‘s. For regular plural nouns that end in s (such as boys, girls, or parents) you only need to add an apostrophe.

The rest of the time, unless you are writing according to a set stylebook, you simply write it how you would say it. If you do that and are consistent throughout your writing, you can’t go wrong!