It can be a little confusing to figure out where the indefinite articles "A" and "An" are used. Here is the proper way to use them.

Note to Reader: A and An rules may differ in different countries. These rules are based in America and may or may not apply elsewhere.

Method 1
Method 1 of 2:

Using "A" Correctly

  1. 1
    Use "A" before all words that begin with consonant sounds. In English, nearly all words that begin with consonants will be preceded by the article "A."[1]
    • For example: a pet, a door, a green onion, a cat, a hysterical joke.
  2. 2
    Understand that there are some exceptions to this rule. Some words may be spelled beginning with vowels but be pronounced with initial consonant sounds. Words that begin in h, y, u, and eu or "e" are common words that can cause confusion.[2]
    • Use "A" when u makes the same sound as the y in you: a union, a unicorn, a used napkin, a usability study.
    • Use "A" when o makes the same sound as w in won: a one-legged man.
    • Use "A" when eu or "e" makes the same sound as y: a European trip, a ewe lamb
    • Do not use "A" when the h is silent.
    Advertisement
  3. 3
    Read words aloud if you're unsure. Sometimes, the way the word looks on the page is not enough to tell you which article to use. Read the word aloud in the way it sounds appropriate to you, and then base your article use on that.
  4. Advertisement
Method 2
Method 2 of 2:

Using "An" Correctly

  1. 1
    Use "An" before all words that begin with vowel sounds. In English, nearly all words that begin with vowels will be preceded by the article "An."[3]
    • For example: an apple, an elbow, an Indian.
  2. 2
    Understand that there are also some exceptions to this rule. Some words may be spelled beginning with consonants but be pronounced with initial vowel sounds. Words that begin in h are the most common causes of confusion, but there are some other letters that can pose a challenge, too.[4]
    • Use "An" before a silent h: an hour, an honorable peace, an honest error.
    • Use "An" before words that are spelled with consonants but pronounced with vowel sounds: an MBA.
  3. 3
    Understand that pronunciation may vary depending on geographical location. For example, British and American pronunciation of certain words varies dramatically, particularly words beginning in h such as "herb." In American pronunciation, the h is silent, so correct usage would be "an herb." But in British pronunciation, the h is pronounced, so correct usage would be a herb.
  4. 4
    Understand that the word "historic" is a special case. There is substantial debate over whether the correct usage is "a historic event" or "an historic event." Nearly all style handbooks and usage guides prefer "a historic event," citing the consonant sound explanation given in this article. However, you may see "an historic" crop up from time to time, particularly amongst British writers.[5]
    • Some American writers will also use "an" with longish words (three or more syllables) beginning with H, where the first syllable isn't accented: "a hypothesis," "an habitual offender."
  5. Advertisement

"A" vs. "An" Usage Chart

Community Q&A

  • Question
    Do I use "a" or "an" before MS?
    Community Answer
    Community Answer
    Use "an" before MS. For example, "An MS patient may have a shorter lifespan than someone without the disease."
  • Question
    How do I know if I should use a or an when in front of a number?
    Community Answer
    Community Answer
    When you say something like "a five-gallon bucket" or "an eleven-piece band", you follow the same rules as outlined in the article.
  • Question
    Is it correct to say: You are an elegant beauty?
    Community Answer
    Community Answer
    Yes, that is correct.
Advertisement

About This Article

Megan Morgan, PhD
Co-authored by:
PhD in English, University of Georgia
This article was co-authored by Megan Morgan, PhD. Megan Morgan is a Graduate Program Academic Advisor in the School of Public & International Affairs at the University of Georgia. She earned her PhD in English from the University of Georgia in 2015. This article has been viewed 627,103 times.
37 votes - 87%
Co-authors: 38
Updated: February 7, 2023
Views: 627,103
Article SummaryX

To correctly use “A” and “An,” use “A” before words that begin with consonant sounds and “An” before words that begin with vowel sounds. For example, say "a pet" or "a green onion," since these word begin with consonants. For words that begin with vowels, use "An," instead, as in "an apple" or "an elbow." However, there are exceptions, including that you also use “A” with words that start with vowels but are pronounced like consonants, and “An” with words that start with consonants but are pronounced like vowels. To learn more from our English Language expert about exceptions to the rule of using “A” and “An,” read on!

Did this summary help you?
Advertisement