There are actually three proper formal addresses for females. These are used in specific situations. When you are addressing letter and email you use it first before the name. The greetings or salutation is the main thing to maintain the status properly. Firsts of all you can sure about gender then it will help you to decide which title is appropriate to address.
You should use Miss when addressing girls and young, unmarried women under the age 30. In some countries Miss is also used to address teachers. The origin of the Miss is derived from the word mistress.
You should use the prefix Mrs. to address any married woman. Using of this title it is clear of the marital status. Some women prefer to keep Mrs. in their title even after their spouse passes away or after their divorce. The title will accompany the husband’s title, first and last name traditionally. This practice is becoming decrease because most of the women like to keep this title even widow or divorce.
You should use Ms. When you unsure about her marital status. It is the safest option to use Ms. You can apply Ms. as a neutral title. It can be used for a woman whether she is married or not.
These are the common ways to address women in a formal or business letter. These shows their regard. These can apply in various situation. At the beginning you must understand the person then greet them with appropriate words. The difference is very closely related.