Hi all. I have my viva in jan, but if I pass will not graduate until Jun. I assume I am not allowed to call myself Dr until after then, but I know people at work will start using it before then ( again if I pass) and I will feel a fraud! When should you start using it? Do people use this title outside of the academic world at all?

I'll wait til all the paperwork has gone through at uni, which should happen before the graduation.... Think it depends from uni to uni though.

I waited until after graduation, which was relatively soon after my viva and minor corrections.

But the key point is when your corrections are approved, and when the resulting paperwork has gone through uni authorities afterwards (Senate or whatever). That happens before graduation.

I notified my bank of my PhD and new title because it's useful for me for ID purposes. But otherwise I don't use the title outside academia/research. Though I'm working as an independent researcher (albeit one with an honorary university affiliation), so not in a university environment.