When do I use a vs an?

Use 'a' before consonant SOUNDS. Use 'an' before vowel SOUNDS. It's about how the word sounds, not how it's spelled. Example: 'a university' (sounds like 'yoo'), 'an hour' (silent H).

A vs An: About Sound, Not Spelling

Q: Is it 'a historic' or 'an historic'?

In American English, 'a historic' is standard because H is pronounced. In British English, 'an historic' is sometimes used. Both are acceptable.

Quick Answer

A = before consonant SOUNDS. An = before vowel SOUNDS.

Key insight: It's about how the word sounds, not how it's spelled. "An hour" (silent H). "A university" (sounds like "yoo").

When to Use "A" (Consonant Sounds)

Use a before words that START with a consonant sound.

A cat, a dog, a book → consonant letters ✓
A university → sounds like "yoo" (consonant) ✓
A European → sounds like "yoo" ✓
A one-time offer → sounds like "w" ✓
A user → sounds like "yoo" ✓

When to Use "An" (Vowel Sounds)

Use an before words that START with a vowel sound.

An apple, an egg, an idea → vowel letters ✓
An hour → silent H (sounds like "our") ✓
An honest person → silent H ✓
An MBA → sounds like "em" ✓
An SUV → sounds like "ess" ✓

Comparison Chart

Article	Use Before	Examples	Tricky Cases
`A`	Consonant SOUNDS	a cat, a book, a tree	a university, a European
`An`	Vowel SOUNDS	an apple, an egg, an idea	an hour, an MBA, an SUV

Tricky Cases Explained

"An hour" but "A hotel"

"Hour" has a silent H (sounds like "our")—use "an." "Hotel" pronounces the H—use "a."

"A university" but "An umbrella"

"University" sounds like "yoo-niversity" (consonant)—use "a." "Umbrella" starts with "uh" (vowel)—use "an."

"An MBA" but "A master's degree"

"MBA" is pronounced "em-bee-ay" (vowel sound)—use "an." "Master's" starts with "m" (consonant)—use "a."

"A one-time" but "An only child"

"One" sounds like "won" (consonant)—use "a." "Only" sounds like "oh" (vowel)—use "an."

Quick Tips

💡 The Sound Test

Say the word out loud. Does it START with a vowel sound? Use "an." Consonant sound? Use "a."

✅ Acronyms

For acronyms, go by pronunciation: "an FBI agent," "a NASA mission," "an HTML file."

Frequently Asked Questions

Is it "a historic" or "an historic"?

In American English, "a historic" is standard (H is pronounced). British English sometimes uses "an historic." Both are acceptable.

What about "a" vs "an" before acronyms?

Go by sound: "an FBI agent" (sounds like "eff"), "a NASA rocket" (sounds like "nassa").

Why is English so inconsistent?

English borrowed words from many languages. The a/an rule is purely practical—it makes speech flow more smoothly.

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A vs An: It's About Sound, Not Spelling