Is it Chris or Chriss

Answer 1

Both are correct. There are two accepted forms for possessive singular nouns ending in s:

Add an apostrophe (') after the existing s at the end of the word: Chris'

Add an apostrophe s ('s) after the existing s at the end of the word: Chris's

Examples:

I met Chris' sister at the party.

I met Chris's sister at the party.

Note: If you are a student, use the form that is preferred by your teacher.