Is there one correct abbreviation for millions in financial terms?

[Quartz]

@Anny_Middon

I do it that way, too.

Related question: Is there a standard way to differentiate between a US billion and a UK billion?

Those are the wrong terms. It’s ‘short scale billion’ and ‘long scale billion’. Wiki has an article here. If you scroll down, you’ll see that the graphic shows the UK as using the short scale.