Is it Boris' announcement or Boris's announcement?

[chomalungma]

Or does it not really matter

What?!

As you pronounce the final s it is Boris's.

No need for the 's on the end if it follows a word ending in 's'. Therefore it's Boris'

Agree with seekingwaxwings. You can hear s twice so you should see it twice.

Grammatically correct is Boris' - it's pronounced Borises but as it ends in S you just put an apostrophe.

Either

Boris’ announcement implies it was made by more than one Bori.

Technically either is correct, but modern usage is to use the extra 's' if you pronounce it. You don't say 'I'm going to Boris' house.' You say 'I'm going to Boris's house.' So you use the extra 'S'

Yeah I think you say Boris-iss but you don’t put an extra on when it is written although I’ve seen people add the ‘s’ in work and academic writing and not been pulled up for it.

It is actually Boris' speech from his arse if that helps you at all.

Boris is not plural. Thankfully there is only one of the gobshite aside from anything else.

Carry on.

Either is correct. However, the single 's' followed by an apostrophe tends to be reserved for more well-known names than Boris Johnson's. Jesus, for example.

Dominic Cummings’

Apostrophe at the end.

Although it can look odd, I admit.

Either.

And here's the relevant section from Oxford Dictionaries:

www.lexico.com/grammar/apostrophe

'With personal names that end in -s: add an apostrophe plus s when you would naturally pronounce an extra s if you said the word out loud:

He joined Charles’s army in 1642.

Dickens's novels provide a wonderful insight into Victorian England.

Thomas's brother was injured in the accident.

Note that there are some exceptions to this rule, especially in names of places or organizations, for example:

St Thomas’ Hospital

If you aren’t sure about how to spell a name, look it up in an official place such as the organization’s website.

With personal names that end in -s but are not spoken with an extra s: just add an apostrophe after the -s:

The court dismissed Bridges' appeal.'

I agree with ScarfLadysBag.

And I love Psychoseverywhere's response

Boris’ announcement implies it was made by more than one Bori

Surely that would be Borises'?

The English language is such that both are technically correct and both look wrong on the page.

So it's Johnson's announcement.

Boris's

Surely that would be Borises'?

No, I meant what I typed.
More than one Bori -> Boris’
More than one Boris -> Borises’

I wonder what the collective noun would be for multiple Borises. An incompetence of Borises?

A circus of Borises

Both correct. Boris' more old fashioned but I prefer it.