Than vs Then: The Quick Rule
Use than for comparisons and then for time. If you are weighing one thing against another — bigger, faster, more, less, rather — the word is than ("She runs faster than I do"). If you mean "at that time," "next," or "in that case," the word is then ("We ate, then we left"). They are never interchangeable, and only than ever follows a comparison.
When to Use "Than"
Than is a conjunction — and, many argue, also a preposition — that introduces the second half of a comparison. It almost always follows a comparative word: an adjective or adverb ending in -er, or one paired with more, less, or fewer, or one of a small set of comparison words such as other, rather, else, and sooner.
- My brother is taller than me.
- This route is quicker than the motorway.
- I'd rather walk than wait for the bus.
- Nobody knows the rules better than she does.
- We have fewer than ten seats left.
- There's no one here other than us.
The tell-tale sign is always a comparison. If you can spot a comparative word nearby — bigger, smaller, more, less, better, worse, rather, other — the correct spelling is almost certainly than.
When to Use "Then"
Then is mainly an adverb, and it handles everything to do with time and consequence. It carries four everyday meanings:
- At that time: "Back then, phones had cords."
- Next / after that: "Preheat the oven, then add the batter."
- In that case / therefore: "If the light is red, then stop."
- In addition / besides: "It's late, and then there's the traffic to consider."
Then can also act as an adjective meaning "at that time" — "the then prime minister" — and even as a noun — "we hadn't met before then." Every one of these uses points to a moment, a sequence, or a result. None of them involves comparing two things.
Correct vs Incorrect: See the Pattern
Seeing the two side by side makes the rule obvious:
- ✓ She's smarter than her boss. — ✗ She's smarter then her boss.
- ✓ We'll finish this, then take a break. — ✗ We'll finish this, than take a break.
- ✓ I'd rather read than watch TV. — ✗ I'd rather read then watch TV.
- ✓ If you're ready, then let's go. — ✗ If you're ready, than let's go.
- ✓ Better late than never. — ✗ Better late then never.
- ✓ First comes love, then comes marriage. — ✗ First comes love, than comes marriage.
Why the Two Get Confused
This is an ear mistake, not a thinking mistake. In ordinary speech, than is unstressed and its vowel collapses to a soft "uh" sound (/ðən/), which is nearly identical to then (/ðɛn/). Because they sound almost the same when spoken quickly, the wrong one slips onto the page. The cure is to pause and ask what the sentence is actually doing — comparing, or telling time?
A Memory Trick That Sticks
Then rhymes with when, and both are about time. So if your sentence could answer the question "when?", use then. If it couldn't — if you're setting two things against each other — reach for than. A second quick test: if you can swap in "next," "at that time," or "in that case" without changing the meaning, the word you want is then.
Tricky Cases and Real Exceptions
"Than I" or "Than Me"?
Both are correct, and the fussy "rule" you may have heard — that "than me" is wrong — is a myth. Traditional grammar treats than as a conjunction with an implied verb ("She's taller than I am"), which is why "than I" sounds formal. But "than me" treats than as a preposition, and that has been standard English for centuries. Use "than I" in formal writing if you prefer; "than me" is perfectly acceptable everywhere else.
One genuine caveat: case can change the meaning. "I like the dog more than him" means you prefer the dog to the man. "I like the dog more than he (does)" means you like the dog more than the man does. When the sentence could be read either way, spell the verb out.
"No Sooner ... Than"
This idiom catches people out because there's no obvious comparative, yet it still takes than, not then: "No sooner had we sat down than the phone rang." The word sooner is doing the comparing, so than is right. (Watch out — "no sooner ... when" is a common error too.)
"Rather Than" and "Other Than"
These fixed phrases always use than. "Rather then" and "other then" are among the most frequent typos in English, but they are always wrong.
"If ... Then"
The logical pairing is always then: "If it's broken, then fix it." Some writers slip in than here because a choice can feel like a comparison, but it isn't — it's cause and effect.
US vs UK: Any Difference?
The core distinction — than for comparison, then for time — is identical in American, British, Australian, and every other variety of English. The only genuine transatlantic wrinkle involves than in one phrase: different. Americans commonly say "different than," especially before a clause ("It's different than I remembered"). British English leans towards "different to," while "different from" is accepted everywhere and is the safest choice in formal writing. Crucially, that debate is between than, to, and from — then is never an option.
The Bottom Line
Comparisons take than; time and sequence take then. When in doubt, test whether the sentence answers "when?" (use then) or sets two things against each other (use than). Get that one question right, and you'll never mix them up again.
