Navy and Marine Corps
Heading
- Sender's symbol
- The SSIC on the second line below the letterhead, starting two inches or more from the right edge; the originator's code or serial under it; the date under that, as "7 Sep 06". (SECNAV M-5216.5 ch. 7 par. 3; ch. 2 par. 16)
- From, To, Via
- "From:" on the second line below the date with two spaces after the colon; "To:" on the next line with six; "Via:" on the next with five. Via addressees are numbered when there are two or more. A second line starts under the first word after the heading. (SECNAV M-5216.5 ch. 7 pars. 6–8)
- Subj, Ref, Encl
- "Subj:" on the second line below, three spaces, every letter capitalized. "Ref:" four spaces and a letter in parentheses for every reference, even one. "Encl:" three spaces and a number in parentheses for every enclosure, even one. (SECNAV M-5216.5 ch. 7 pars. 9–11)
Navy and Marine Corps
Text and signature
- Paragraphs
- Every paragraph is numbered or lettered: 1., a., (1), (a), then the same four underlined. Each new subdivision starts under the first letter of the paragraph above; continuation lines return to the left margin. (SECNAV M-5216.5 ch. 7 par. 13; figure 7-8)
- Later pages
- The subject line is repeated at the top of each page and the text resumes on the second line below it. Page numbers are centered ½ inch from the bottom edge, starting with 2. A paragraph is split only with two lines on each page, and a signature page carries at least two lines of text. (SECNAV M-5216.5 ch. 7 pars. 13, 16, 17)
- Signature line
- Starts at the center of the page on the fourth line below the text: initials and last name in capitals, no rank and no complimentary close. A title, "Acting" or "By direction" goes on the lines under it. (SECNAV M-5216.5 ch. 7 par. 14)
- Copy to
- At the left margin on the second line below the signature line; the addressees listed below it. (SECNAV M-5216.5 ch. 7 par. 15)
Navy and Marine Corps
Endorsements and memorandums
- Endorsements
- FIRST, SECOND, THIRD ENDORSEMENT. On the same page it follows the basic letter and may omit the SSIC, the subject and the basic letter's identification. On a new page it goes on the endorser's letterhead, repeats the SSIC, names the basic letter in the endorsement line ("SECOND ENDORSEMENT on NAS Meridian ltr 5216 Ser 11/273 of 22 Apr 15"), uses the basic letter's subject, and continues the page numbering. Added references and enclosures continue the lettering and numbering. (SECNAV M-5216.5 ch. 9; figures 9-1, 9-2)
- Memorandums
- Memorandum for the record: plain paper, dated, signed, with the signer's organizational code. Plain-paper memorandum: the date on the sixth line ending at the right margin, then MEMORANDUM and the From-To headings. Letterhead memorandum: the standard letter's format with MEMORANDUM above From. (SECNAV M-5216.5 ch. 10; figures 10-1, 10-3, 10-4)
From one level to the next
A memorandum that has to pass through other offices on its way up or down follows the rule below. The generator keeps a reply on the page it replies to when it fits; when it does not fit, the reply starts a new page in the format the manual gives for that case.
- Navy and Marine Corps. FIRST, SECOND, THIRD ENDORSEMENT. On the same page it follows the basic letter and may omit the SSIC, the subject and the basic letter's identification. On a new page it goes on the endorser's letterhead, repeats the SSIC, names the basic letter in the endorsement line ("SECOND ENDORSEMENT on NAS Meridian ltr 5216 Ser 11/273 of 22 Apr 15"), uses the basic letter's subject, and continues the page numbering. Added references and enclosures continue the lettering and numbering. (SECNAV M-5216.5 ch. 9; figures 9-1, 9-2)
Each manual does this differently: every service's rule, side by side.
Department of War letterhead: what each source says
Navy and Marine Corps letterhead starts here with the Department of Defense seal in black, which is what the Department of the Navy manual prescribes. Either seal, black ink, your own letterhead image or plain paper is one click away. Which one is right for you is your command's call; this is what has been published, with the dates.
- Navy and Marine Corps (16 May 2018). The Department of the Navy manual says letterhead "shall bear a one-inch in diameter seal of the DoD." (SECNAV M-5216.5 ch. 2 par. 12b(1))
- Department of War (1 October 2026). "Department of War and Military Seals are protected by law from unauthorized use, and these seals may NOT be used for non-official purposes." (war.gov, Branding and Trademarks)
The seals appear only inside the document you make. Military Toolkit is not affiliated with the Department of War, the Department of Defense or any Military Service, and a memorandum made here is official only when an authorized person signs it for an official purpose.
How the layout is checked
Line breaks are computed with the advance widths of the PDF standard fonts (Adobe's Core 14 font metrics). Times New Roman, Arial and Courier New share those widths with Times, Helvetica and Courier, so a line that fits in the preview fits in Word.
On 1 October 2026 the Word files of five sample documents were opened in Microsoft Word and saved as PDF; every word of the text sat within 0.3 point of its position in the generator's own PDF, with the same page breaks.
The PDF is the finished document: every line is placed where the manual puts it. The Word file is the same document left open for editing, with real paragraphs, indents and tab stops, so a change you make there keeps the format. Page breaks follow the manuals as well: at least two lines of a paragraph on each side of a break, and a signature block never alone at the top of a page.
Sources
- SECNAV M-5216.5, Department of the Navy Correspondence Manual, June 2015, with Change Transmittal 1 of 16 May 2018. Chapter 2 and Appendix C (stationery), chapter 7 (standard letter), chapter 9 (endorsements), chapter 10 (memorandums). Listed on the Department of the Navy issuances page on 1 October 2026.
- MCO 5216.20B, Marine Corps Supplement to the Department of the Navy Correspondence Manual, 10 March 2016, with Administrative Change 4 of 29 September 2025. Section 2, Standard Letter. Section 2 has Marines prepare standard letters in the Navy manual's format.
Read on 1 October 2026. A command supplement or a local operating instruction can add to these rules; where it does, it governs.
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