BE speakers mostly write Thomas's and Charles's; AE speakers prefer Thomas' and Charles'.
See also the third of the Similar Threads below, and read more about it here.
I'm confused because I've seen examples like Thomas' and Charles's? Which one is correct? Is there a rule?
1. Always use 's after names ending in S.
2. Always use 's after names ending in S if you pronounce the final S.
3. Always use 's after names ending in S unless the pronunciation of the final S will result in a repeated syllable (such as Jesus-es or Moses-es.
4. Use only an apostrophe after the final s in a name.
I doubt there will ever be total agreement on this subject. All one can do is pick a rule one likes and be consistent in one's own writing.
I use rule #2.
Last edited by Rover_KE; 08-Aug-2013 at 22:08. Reason: Fixing typo
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