Many businesses and news outlets use the guidelines set out in the Associated Press Stylebook (also known as AP style). But how should you write dates in AP style? In this post, we explain:
- The basic date format recommended in AP style.
- How and when to abbreviate months.
- When to include the day of the week in a date.
- Setting apart years in a date.
- When to use an apostrophe with decades and centuries.
- Whether to use “On” before a day or date.
- Whether it’s okay to start a sentence with a year.
For more information on all the above, watch the video or read on below.
1. Writing Dates in AP Style
The most important aspect of dates in AP style is to use Arabic numerals for dates and years instead of writing them out in full as words:
The event was held on June 1, 1987. ✓
The event was held on the first of June 1987. ✗
In addition, in AP style, you should not use ordinal numbers in dates:
Since June 1, the company has been… ✓
Since June 1st, the company has been… ✗
As a default, it also suggests using the US date format since the AP Stylebook is a US English style guide.
However, you can also adapt the guidance here if you’re writing for an audience that uses a day-month-year date format, such as in the UK. With this in mind, we’ll note issues below where UK conventions for writing dates would differ from those recommended in the AP Stylebook.
2. Months in AP Style
AP style recommends abbreviating any month more than five letters long when writing a date (i.e.,
Jan., Feb., Aug., Sept., Oct., Nov., and Dec.). However, you don’t need to abbreviate March, April, May, June, or July:
Jan. 1, 2014 ✓ June 6, 1982 ✓
January 1, 2014 ✗ Jun. 6, 1982 ✗
If you refer to a month without an exact date, though, always write it in full:
She graduated in November 2019. ✓
The August holidays were sunny and warm. ✓
The exception to this rule is tabular material, where you can use three-letter forms with no periods (i.e., Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov, Dec). The same applies to days of the week (i.e., Mon, Tue, Wed, Thu, Fri, Sat, Sun), which should always be written in full elsewhere.
3. Days of the Week in AP Style
You don’t usually need to give the day of the week with a date. However, if you do, use a comma to set it off from the rest of the date:
The pair met Sunday, Oct. 22, 2017. ✓
The pair met Sunday Oct. 22, 2017. ✗
In addition, AP style recommends using a day of the week to avoid vague time elements, such as “today,” “tonight,” “tomorrow,” or “yesterday”:
The main street was closed Tuesday for a parade. ✓
The main street was closed yesterday for a parade. ✗
And if you’re referring to an event more than a week from your publication date, give the date instead of the day of the week:
The parade, which took place on May 14, drew a crowd of 14,000. ✓
Last Tuesday’s parade drew a crowd of 14,000. ✗
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This helps to ensure clarity for the reader about the date in question.
4. Commas and Years in Dates
The AP Stylebook recommends setting apart the year in a date with commas. You can see this in the examples above, where we put a comma between the date and the year to separate the numerals.
However, if the sentence continues after the year, you also need a comma after the date. For instance:
Born Jan. 17, 1984, Mr. Albert went on to… ✓
And if you only mention a month and year, no commas are required:
The scheme was announced in June 2020. ✓
It’s worth noting that these commas are much rarer in UK English. As such, you may want to ignore this rule if you’re writing for a UK audience (or readers in another country where day-month-year dates are standard).
5. Apostrophes in Centuries
When abbreviating a decade, AP style requires an apostrophe at the start:
The ‘beehive’ hair style was popular throughout the ‘60s. ✓
However, you should not use one before the “s” in decades or centuries:
The early 1800s were a time of rapid change. ✓
During the 1950’s, there was a post-war baby boom. ✗
This is because the “s” here indicates a plural, not possession.
6. Using “On” Before a Date
AP style recommends omitting the word “on” before a day or a date:
The Council met Tuesday to discuss the plan. ✓
The Council met on Tuesday to discuss the plan. ✗
However, you should use “on” with a date if it’s the first word in a sentence:
On 12 July, the new law came into effect. ✓
And you should include it to prevent ambiguity. In the following, for instance, we include “on” to clarify that we’re referring to “Dr. Freeman” on a specific day, not someone called “Dr. Freeman Tuesday”:
He met with Dr. Freeman on Tuesday. ✓
He met with Dr. Freeman Tuesday. ✗
As with setting apart the year with commas, though, omitting the “on” in this context is rarer in British English. So whether you want to follow this rule may depend on where your audience is based and your chosen dialect.
7. Starting a Sentence with a Year
Generally, AP style forbids starting a sentence with a numeral, recommending either spelling out the number or rephrasing the sentence. But it makes an exception for years, which can go at the start of a sentence:
2009 was a good year for Barack Obama. ✓
As such, it’s fine to do this as long as the sentence reads smoothly.
Expert AP Proofreading
We hope this post has clarified the basics of dates in AP style. And if you’d like help proofreading documents in AP style, our editors are available 24/7. Submit a 500-word sample document for free to find out more.