Month Abbreviations in Dates
Month names are normally written in full in running prose, while abbreviated forms are useful where space is limited. Microsoft’s house style uses three-letter forms such as Jan, Feb, and Sep without periods.
Prefer full month names in ordinary prose; when space requires abbreviations, use a consistent approved set for the chosen style.
Key details
Important caveats
Abbreviation Boundary
Its constrained-space forms are three-letter month abbreviations without periods; other style guides may differ.
Full Form Boundary
Microsoft recommends full month names unless space is extremely limited.
Further guidance
Practical Application
Use full month names in ordinary prose unless space, a table, interface, or house style calls for abbreviations. When abbreviating, use the approved set for that style and keep punctuation and abbreviation choices consistent across comparable dates.
Reader Check
Is there a real space/style reason to abbreviate the month, and does the document use one consistent abbreviation system?
Worked Example
A narrative sentence can write “September 28, 2026” in full, while a compact table may use the house-approved abbreviation consistently in every row rather than mixing “Sept.”, “Sep”, and full month names.
Sources and evidence
Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.
- Date and time terms — Microsoft Style Guide (opens in a new tab)Microsoft · Official Microsoft house-style guidance for dates and times, including date ordering and formatting examples.