Williams’ or Williams’s?

Williams’ is the singular possessive of the last name Williams, which you should use when following AP Style. E.g., “Mr. Williams’ wife is a vet.” Also, Williams’s is the version to use according to the Chicago Manual of Style. E.g., “Mrs. Williams’s dog died yesterday.”

The following chart provides a helpful overview of the different forms of the surname Williams.

Singular possessiveWilliams’ / William’s
Plural possessiveWilliamses’

There are two forms of the possessive that you can use to refer to one member of a Williams family. Also, if you are referring to more than one member, you can use the term Williamses.

Here are some examples of the different forms in context.

  • Singular: Harry Williams has found a new job in a bar.
  • Plural: The Williamses from number 34 are throwing a party this weekend.
  • Singular possessive: Peter Williams’ mother is a lawyer.
  • Singular possessive: We are heading to John Williams’s apartment to watch the game.
  • Plural possessive: The storm damaged the Williamses’ roof last night.

As you can see, when referring to one person from a Williams family, you can use Williams’ or Williams’s unless you are following a specific style guide. However, make sure that you are consistent with the version you use.

Peep reading the rest of the article to learn more about using the possessive and plural forms of the surname Williams.

We’ll also show you many example sentences to make the rules easy to understand.


The word Williams’s is the singular possessive form of the name surname Williams.

It is the more common form in both the US and the UK. Moreover, it is the form you should use when following the Chicago Manual of Style.

You can use the singular possessive to refer to things that a member of a Williams family owns.

Here are some examples:

  • Mary Williams’s eyes are a beautiful blue color.
  • Shane Williams’s television is the biggest I have ever seen.
  • Mrs. Williams’s car is a classic and she maintains it well.
  • Do you have a copy of Robert Williams’s book?
  • I visited Professor Williams’s office to discuss the assignment.
  • Susan Williams’s art collection is impressive.

Also, William can also be a first name. Therefore, here are some examples of Williams’s being used as the singular possessive for a person named William:

  • Williams’s handwriting is uniquely elegant, almost like calligraphy.
  • Williams’s latest painting has been featured in the city gallery.
  • Everyone loves Williams’s sense of humor; he’s always the life of the party.
  • Williams’s presentation at the conference was incredibly insightful.

Furthermore, when the following word begins with “s,” some people drop the “s” from Williams’s.

  • Mr. Williams’ social life is non-existent.
  • I met Williams’ sister at the event last night.
  • Julie Williams’ store is just around the corner.
  • Have you tried the Williams’ signature dessert?
  • We attended Williams’ seminar on digital marketing.
  • The Williams’ son has just started his college journey.

However, if you do this, you must be consistent and do it throughout the text.

That means you need to use Williams’ no matter if the word following starts with an “s” or not. You cannot mix between Williams’ and Williams’s in a text.

Now, let’s have a closer look at the variation Williams’.


The term Williams’ is a singular possessive form of the surname Williams. Therefore, you use it when you want to say that things belong to one person with the last name Williams.

  • Sally Williams’ grades have been improving this semester.
  • Mr. Williams’ character is warm and friendly.
  • Derek Williams’ guitar collection is quite impressive.
  • Mrs. Williams’ garden is the talk of the neighborhood.
  • I borrowed Jennifer Williams’ notes to study for the test.
  • Mr. Williams’ desk is always organized and neat.
  • We attended Peter Williams’ wedding last summer.

Furthermore, you should use Williams’ if you are writing a text that follows AP Style.

You should also note that William can also be a first name. Therefore, you can also use Williams’ to refer to a person named William and his possessions.

Here are some examples:

  • Williams’ handwriting is truly remarkable; it looks like a font.
  • I heard Williams’ new song on the radio, and it’s fantastic.
  • Have you tried Williams’ homemade cookies? They’re the best.
  • We’re going to Williams’ party this weekend; are you coming?
  • Williams’ jacket was left behind after the meeting; I’ll keep it for him.

Remember that both Williams’ and Williams’s are correct possessives for the first name or surname William. You can choose which version you want to use if you don’t follow a certain style guide.