If you are more personally acquainted, "Dear Mary and John,"
Never separate the man's first and last names - in other words, do not write the couple as "John and Mary Jones," only as "Mary and John Jones."
To address them formally, [for example, if they were both male] you could write "Dear Mr. T and R Smith"
Additional Info:
A somewhat antiquated tradition which is still in use (particularly by attorneys) is this:
For two men:
Dear Messrs. Smith
Dear Messrs. Smith and Jones
For two women:
Dear Mesdames Smith
Dear Mesdames Smith and Jones
Many same-sex married partners have the same last name.
If the couple is John and Fred Smith, then address it to "Messrs. John and Fred Smith." It does not matter which name (John or Fred) comes first.
If the couple is Mary and Emily Jones, then address it to "Mesdames Mary and Emily Jones." Again, you can put first whichever name you wish.
If the couple does not share the same last name (many opposite-sex couples do not either), then you can address it "Messrs. John Smith and Fred Jones" or "Mesdames Mary Smith and Emily Jones." Again the order of the names is up to you.
The same way you would address any other married couple:
Dear Lucy and Sally
Dear Ms. and Ms. Jones
Dear Mrs. and Mrs. Jones
Dear Lucy and Sally Jones
An older tradition dictates that a letter addressed to two women should be written as follows:
Mesdames Jones
Mesdames Lucy and Sally Jones
If they both have the same last name, it's: "Messrs. Jones" for two men and "Mesdames Jones" for two women. If they have different last names, it's: "Messrs. Smith and Jones" for two men and "Mesdames Smith and Jones" for two women.
The plural of Mrs. is "Mesdames". Some examples are:
If they have the same last name:
Kim and Janet Smith
If they have different last names:
Ms. Kim Smith and Ms. Janet Jones
You'd address them by their title and last name: E.g Mr Steinberg. If you know them well, you'd use their first name.
You would use the first name of the husband and the first name of the wife. This is how you address a Japanese married couple through a letter.
The proper way to address a letter to a married couple with a suffix at the end of the name is to adopt the traditional rule of keeping the man's first and last name together. Mary and John Smith This is the proper way to address a married couple when using this format. So it follows that: Mary and John Smith Jr. Mary and John Smith III Mary and John Smith, Esq. would also be the proper outline.
You can address a letter to two doctors as: Drs. John & Jane Doe.
No, it should be Mr. & Mrs. John Doe. You only use 'Ms.' if you are addressing a letter to someone you do not know is married or single or; in these modern times some women prefer you address them as Ms.
In correspondence, addressing a married couple is : " Mr and Mrs John Smith " - the first name of the husband is the only one used. It is incorrect to address a letter to a married woman as " Mrs. Mary Smith. " A married woman traditionally takes the name of her husband and so a letter to her would properly read, " Mrs. John Smith." Surreyfan
Frau
You can address it to Mr and Mrs. Smith. You could address it is as the Smith Family. Or you could address it as Mr. Smith and Family.
You can address a letter Dear Fred and Bertha (or whatever the actual names are). Personally, I often address my letter Dear Folks. That way there won't be any dispute about why I put Fred's name before Bertha's.
Unfortauntely, we don't know the address of your land lady. However, If you're trying to address a letter to your land lady you'd just address her as Ms. or Mrs. depending on if she married or not.
By their first names, if it's informal. Otherwise Dear Mr ...... and Mrs/Miss/Ms .........
You can address them as 'Sir' if they are a man, ' Miss' if you do not know if the lady is married or not, 'Madam' if you know the lady is married. If you are writing a letter, and you do not know the gender, you can address him/her as 'Dear Sir/Madam'. If you do not want to use any of the above, you may use 'excuse me'. Hope this answers your question :)
You address the letter to the couple like if they're names are Robert and susy Henderson then you can write Mr. and Mrs. Robert Henderson and family :) That's what i did for my brother's graduation cards