What form of address in professional correspondence do you consider more appropriate: informal or formal?

In professional correspondence, it is preferable to use formal address, especially if you do not know the recipient personally or if the correspondence concerns official matters. Formal address shows respect and professionalism.

Informal address is appropriate in teams with a friendly atmosphere or during long-term cooperation when trust relationships are established.

Example of formal address:

Dear Ivan Ivanovich,

Thank you for your question...

Example of informal:

Hi, Ivan!

Thanks for the information...