I prefer formality, especially when receiving a circular letter from a bank informing me of some further inconvenience in their service.
Many years ago I addressed a letter of complaint addressing the Chairman of British Gas by his Christian name, asking him how he liked it, and pointing out that they were not my "energy adviser", as their last letter had claimed, but one of my energy suppliers.
But I was amused to receive a series of letters from a bank with which I had no connection, addressed to Mr. Gone Away. My reply, adopting the name they had given me and seeking details of my sort code and account number, did not receive a reply.
Formal letters using my first name


