Comma in Dates
Comma use in dates is tied to the date order and house style. Microsoft’s month–day–year convention includes a comma before the year, while Australian Government day–month–year style omits a comma. Apply the punctuation that belongs to the chosen date format.
In month–day–year prose, a comma commonly separates the day from the year (“July 31, 2016”). In day–month–year styles such as Australian Government style, no comma is used (“31 July 2016”).
Key details
Important caveats
Order Boundary
Do not transfer the comma rule from one date order to another automatically.
Style Boundary
Microsoft and Australian Government guidance illustrate different punctuation conventions tied to their preferred date orders.
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 · Microsoft house style for AM/PM and human-facing time notation
- Dates and time — Australian Government Style Manual (opens in a new tab)Australian Government Style Manual · Australian Government guidance for day–month–year dates, ordinal dates, decades, centuries, time zones, and en-dash spacing in date/time spans