'Dear Mayor Smith' is acceptable for ordinary communication. 'Your Honor' is a more formal salutation. In Canada (and, I think, in Britain also) it might be better to use 'Your Worship.' (A mayor historically had the powers of a magistrate.) Check with the municipality's office of protocol when in doubt.
Mr. Mayor
Salutations are gestures or greetings that are meant as an acknowledgment. The proper salutation for a current mayor is Mr. Mayor or Madam Mayor.
"Your Honor" or "Mr. (Mrs.) Mayor"
Dear Mr. Mayor or sometimes, such as New York, Your Honor.
madame mayor
The mayor is generally referred to as Sir, or Mister Mayor. His wife, unless she holds a political office herself, is called Mrs. Whatever-her-last-name-is. - wjs1632 -
Mr. John Jones.
What is the proper salutation for a register of wills, e.g. Honorable John White?
the correct salutation for two men is Messrs
When addressing a female mayor and multiple council members, it is good form , regardless of gender, to address the mayor first. An example would be: The honorable (insert formal name), Mayor of(name of city) and members of the (name of city) City Council.
Hello.
Your Honor