What is the possessive form of a name ending in s?

Names ending in “s” can follow the same rules as other singular nouns. The possessive is formed by adding an apostrophe and an “s” (e.g., “Rhys’s book”).

Some style guides, however, recommend adding only an apostrophe after certain names ending in “s” depending on whether an extra syllable sounds natural (e.g., “Jesus’ followers”).

To avoid inconsistency, we recommend adding an apostrophe and an “s” to all names (e.g., “Jesus’s followers,” “Mavis’s car”).