Abbreviations for Years: How to Use BC, AD, BCE & CE Correctly

Historically speaking…

When even native speakers get a certain aspect of English mixed up, you can bet it’s tricky for English language learners to master. This is the case with writing and saying years. Why do we have more than one word to represent an era? Why don’t they have the same position in a sentence? How do we punctuate and capitalize these abbreviations? Let’s clear things up for our students (and possibly for ourselves).

1. Meaning

  • BC stands for “Before Christ” and represents the years before Christ was born
  • AD stands for “Anno Domini,” which is Latin for “the year of our Lord,” and represents the years after Christ was born
  • BCE stands for “Before Common Era,” “Before Christian Era,” or “Before Current Era” and represents the time before the last 2015 years (at the time this was written)
  • CE stands for “Common Era,” “Christian Era,” or “Current Era” and represents years 1–2015 (at the time this was written)

BC and BCE represent the same time frame, but with BCE, the religious aspect is removed. The same goes for AD and CE (the religious aspect is removed with CE).

2. Position

  • 300 BC
  • AD 2015
  • 300 BCE
  • 2015 CE

BC, BCE, and CE come after the year. Write or say 300 BC or 300 before Christ, 300 BCE or 300 before common era, and 2015 CE or 2015 common era. However, AD comes before the year, so write or say AD 2015 or anno Domini 2015. This is because anno Domini is Latin for the year of our Lord, and we always say the year of our Lord before the year (so the year of our Lord 2015).

Is 2015 AD ever correct? Many people (myself included) were taught that AD stood for after death (after the death of Christ). Some people do write or say AD after the year, but as this is technically incorrect, it is far better to write or say AD 2015.

3. Punctuation & Capitalization

Is it BC or B.C.? BCE or B.C.E.? Well, it depends on which style guide or dictionary you follow. Merriam-Webster Dictionary (American English) lists these entries with capital letters and no periods (e.g., BC), but notes that they are often punctuated and/or written in small capitals (e.g., B.C.). Oxford Dictionary (British English) and Oxford Canadian Dictionary (Canadian English) also list these entries with capital letters and no periods (e.g., BC) and notes they are often written in small capitals, but they don’t list periods as common usage.

A popular American style guide, The Chicago Manual of Style, has these entries in capital letters with no periods (e.g., BC). This is consistent with many other types of abbreviations that they list (e.g., US, UK, WA, etc.). In my role as an editor, I’ve noticed that there is definitely a movement away from unnecessary punctuation.

Practice

Show your students examples of these dates in a lesson and then go over the explanation above. Our Famous Places lesson on Nazca Lines includes BC and AD in the first paragraph of the reading. (In fact, editing this lesson for our new English App is what inspired this blog post!)

81_Nazca-Lines_US

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36 comments

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  1. lluis.enrique.monzo@gmail.com'

    lluis says:

    Jun 05, 2018 at 5:07 am

    Thank you for your explanation. I have a doubt regarding when is appropriate to use these abbreviations and when not?
    I mean, if we are writing about the date a building that was built in the twentieth century we would never use them. If we are writing about the date a building that was built in the Roman Empire we would surely use them. But, what if we are writing about the date a building built in the Reinassance. Should we use them or not?
    I would like to write: “The domes of the Pantheon in Rome (118-126), Hagia Sophia (532-537) and Santa Maria del Fiore (1296-1436) are well-known historical examples”
    but I do not know if I need such abbreviations or not. What would you recommend me?

    Reply

    • Tanya Trusler says:

      Jun 05, 2018 at 3:10 pm

      Hi Iluis,

      It’s really up to you whether you want to include dates or not. It could depend on the context (an architectural magazine, for example, might include dates even for modern buildings), but generally speaking, you’re correct that we’d usually use them for historical buildings.

      I’d consider the buildings in your example historical, and I think it sounds natural to include the dates. I’d suggest including the word “built” in the first example, but I don’t think you’d need to say AD for each one if the context was clear. You could also choose to include AD only for the first one if the context wasn’t clear. Note that en dashes, not hyphens, are preferred when writing dates.

      E.g., “The domes of the Pantheon in Rome (built AD 118–126), Hagia Sophia (532–537) and Santa Maria del Fiore (1296–1436) are well-known historical examples.”

      Reply

  2. Lwoodhatch@gmail.com'

    Len says:

    Apr 12, 2018 at 8:29 am

    In UK writing should it be in Italics or roman?

    Reply

    • Tanya Trusler says:

      Apr 13, 2018 at 1:04 pm

      Hi Len,

      I’m not that familiar with UK style choices, but I do have a copy of The New Oxford Style Manual on my desk and have looked it up for you. They advise writing BC, AD, BCE, and CE in small caps with no periods/points. BC, BCE, and CE follow the date and AD precedes it, as advised above. As for italics, they say, “Small capitals are used for specifying eras. In an italic context they may be set in italics; otherwise, small capitals are generally set in roman type.”

      Reply

  3. pinkirani1291@gmail.com'

    Komal says:

    Mar 07, 2018 at 8:27 am

    I have a problem, I don’t know how many years AD, BC and BCE stands for? If I would say this happened in 209 BC, so how many years it means from now?

    Reply

    • Tanya Trusler says:

      Mar 07, 2018 at 6:23 pm

      Hi Komal,

      I found this information on the sciencing.com site (https://sciencing.com/calculate-years-across-bc-ad-8433373.html):

      Calculating Years Across B.C. and A.D.
      “If you have a math problem that requires you to calculate years across B.C. and A.D., it’s crucial to adjust for the fact that there was no year 0. For example, if you need to work out how many years are between January 1, 200 B.C. to January 1, A.D. 700 you add the BC and AD numbers. The calculation is 700 + 200, which equals 900 years. However, you still have to adjust for the absence of year 0. You do this by removing 1 from your answer, so 900 minus 1 is 899.”

      According to these rules, 206 + 2018 = 2224 – 1 = 2223.

      Reply

  4. touchhrushi@gmail.com'

    Hrushikesh says:

    Feb 21, 2018 at 4:22 pm

    While writing a history text do I have to use AD for all the dates in entire document ?

    Reply

    • Tanya Trusler says:

      Feb 21, 2018 at 7:08 pm

      That depends on the style guide you’re following. If you’re writing for a university, they’ll have a style manual or house style sheet that writers should follow, such as APA format or MLA format. Publishers often follow the Chicago Manual of Style. If you’re writing on your own, you can make your own rules somewhat (as long as they’re logical and, especially, consistent). In general, unless you’re going back and forth between AD and BC/BCE, I’d say you’d only need to say AD once or twice and the rest would be clear from the context.

      Reply

  5. writer@floreby.se'

    Lennart says:

    Feb 16, 2018 at 4:01 am

    Great explanation, thanks! I have a question though: If you need to say “He was born in the 900s AD”, how would you write that correctly? It doesn’t feels right to write “He was born in the AD 900s”.

    Reply

    • Tanya Trusler says:

      Feb 20, 2018 at 2:34 pm

      Hi Lennart,

      That is an excellent question. Unfortunately, CMOS doesn’t provide an example of this. My guess is that we would say “AD 900s” (and Google has many references to it used this way), but I would suggest dropping the “AD” and just say “He was born in the 900s.” Hopefully it would be clear from the context (where you could include a specific date with AD). Another option is to style it “in the tenth century AD” but, even then, CMOS recommends dropping the “AD.” Hope that helps!

      Reply

  6. liwellv@gmail.com'

    Liwell says:

    Jan 15, 2018 at 7:39 am

    Well Elaborate,thank you

    Reply

  7. uxtenz12@gmail.com'

    Egbaji Austin says:

    Jan 13, 2018 at 9:34 am

    Very clear now, thanks..But how do I get your app? I’m in Nigeria.

    Reply

    • Tanya Trusler says:

      Jan 15, 2018 at 11:45 am

      Hi Egbaji, you can use this link to subscribe to our site anywhere in the world: https://esllibrary.com/sign_up

      Our site is mobile-friendly, but we also have an app coming out in March 2018. Please let me know if you have any other questions.

      Reply

  8. tbatinovic@yahoo.ca'

    Tanya says:

    Jan 04, 2018 at 1:05 am

    Best explanation, thus far. Thank you.

    Reply

    • Tanya Trusler says:

      Jan 04, 2018 at 6:49 pm

      Thanks for your comment, Tanya! Nice name too. ;)

      Reply

  9. priyanshumandan@gmail.com'

    priyanshu says:

    Dec 04, 2017 at 12:43 pm

    understood at once….! thnks human

    Reply

  10. ayarigajohnson123@gmail.comm'

    Johnson ayariga says:

    Oct 17, 2017 at 1:15 pm

    All questions had answered

    Reply

  11. bh0456@yahoo.com'

    Barbara Hayes says:

    Oct 12, 2017 at 11:35 am

    So many questions answered – Thank You!

    Reply

  12. gcass48@gmail.com'

    Grace says:

    Oct 10, 2017 at 10:48 pm

    Clear, concise and helpful information, thank you!

    Reply

    • Tanya Trusler says:

      Oct 11, 2017 at 12:10 pm

      You’re welcome, Grace! Thanks for commenting.

      Reply

  13. satishjain43@gmail.com'

    Satish jain says:

    Oct 04, 2017 at 2:22 pm

    At last understood this! Thanks for explaining.

    Reply

  14. faridshaikh5@gmail.com'

    Farid says:

    Sep 26, 2017 at 4:08 pm

    I have seen mostly used in Religion historical book… anyway even I didn’t know about it. But now I know!

    Reply

  15. luckykr.666666@gmail.com'

    Ravi Kumar says:

    Sep 22, 2017 at 1:02 pm

    Thank you so much for your great explain, the way of giving example is amazing :)

    Reply

  16. amudhasubbu@yahoo.com'

    Amudha says:

    Sep 07, 2017 at 5:17 am

    Superb
    Good clarity

    Reply

  17. prabhaprasanna12@gmail.com'

    Prabha says:

    Jun 29, 2017 at 1:27 am

    Really it’s worth full information thank you

    Reply

  18. shuchita93@gmail.com'

    Shuchita says:

    Jun 07, 2017 at 10:43 am

    Thanks a lot…It helped…:-)

    Reply

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