Guidelines for Names and Titles: The salutation should typically use the person's last name, along with a "Mr." or "Ms." In general, avoid using "Mrs." or "Miss" unless you are certain of how the woman wants to be addressed. When in doubt, default to using "Ms."
Business Letter Format: Review a formatted business letter with information on what to include in each section of your letter. When you are writing a business letter, it's important to include an appropriate salutation at the beginning. This is true whether you send your message via email or through the mail. Using an appropriate greeting sets the tone for your letter and shows the recipient that you understand basic rules of business etiquette.