Etiquette question - whether to use first name in email to someone you don't know

[Autumnalsky]

I thought there used to be an etiquette section of mumsnet but I can't find it. If there is one, then MN, would you move this thread to there, please?!

If you're emailing your MP or local councillor, or other person whom you don't know and whom you're contacting in their professional capacity, is it the norm to put their first name or Mr/Ms and their surname?

Thank you!

I would. Then if they replied and signed off with their first name I would sue that in the follow up email

Surname of you are writing to someone unknown in a formal capacity.