Although formats vary among organizations, a memo minimally has a heading and a body. In addition, it may also have a signature line, reference initials, an attachment notation, and a courtesy copy notation.
Good memos begin with the most important ideas, are clearly and logically organized, and are concisely written.See Example (.pdf)
A typical memo heading usually contains the following:
The order, spacing, and placement of heading elements vary considerably. Some memos insert the "Subject" immediately after "To," while others place the "Date" in that location. Still others omit "From" and have a typed name and signature at the end of the memo.
In printed memo forms, headings do not have colons.
The names of sender and receiver do not require courtesy titles ( Mr., Mrs., Ms., or Miss) although Dr. is sometimes used.
Subject lines are as specific as possible, leaving no uncertainty regarding the purpose of the memo.
The heading may also contain a reference line or block. Short reference lines appear two lines below the Date element; extensive references have their own lines, usually after the Subject element.
Paragraphs are single-spaced with a double space between them. Either a block or indented format is employed. Headings, lists, and other emphasis techniques are useful, especially in long memos.
Use of indentions in the body of the memo depends upon the style preference of the organization.
Signature lines in memos do not require courtesy titles.
Normally, a memo has no signature line--the sender's name is given in the heading after From. If desired, however, a signature line (with either printed or handwritten name or initials) may be inserted two lines below the final line of the memo body.
When reference initials are used in memos, they usually are just the inputter's initials and appear in lowercase letters two lines below the final line of text (or signature line):
If the reference initials also include the author's initials, they appear as one of the following:
TLM/rgn TLM:rgn tlm:rgn
In those rare instances when a memo is written by someone other than the sender, the sender's initials appear first, the writer's initials next, and the inputter's initials last:
Attachment notations are rather uncommon in memos.
Attachment notations, if used, appear on the line immediately below the reference initials:
TLM/rgn EBD/TLM/rgn Attachments(2) 2 Attachments
Technical memos with several attachments may list those attachments after the attachment notation.
Courtesy Copy Notation
The courtesy copy notation appears two lines below the reference or attachment notations:
cc cc: Copy to Copies to
A memo sent to several individuals may simply list their names after "To" in the heading and omit the "Distribution" designation.
As an alternative, memos sent to a large number of readers may have Distribution appear after To in the heading, followed by a listing of the designated readers' names and (if appropriate) their departments.