It is amazing how much confusion such trivial words as then and than can generate. The fact that many dialects pronounce them very similarly doesn’t help, especially for those without extensive background in written English. But if we want our prose to be as clean and elegant as possible, it is important that we know when to use which one, even if our characters occasionally aren’t as educated as we are and mix them up.
Use then if the situation relates to time, order, or consequences. One of the most common uses of then is in if X then Y statements, although technically then isn’t needed here unless you are coding. But that type of usage relates consequences.
An example regarding time:
The boy carefully wrote and edited his post. Then he shared the post link with his friends.
This indicates the second statement happened after the first. But you can also use it within a sentence.
Jill filled the pail with water then poured it over Jack's head.
And for order:
The search results list newer posts then older ones.
Use than in comparative situations, regardless of the type of comparison.
You have more money than I do.
That was a simple one. This is a more complicated sentence:
The essence of his magic was tainted with evil, making it blacker than tar and just as prone to tainting everything around it.
The horse was sure she could get more upvotes ____ any puppy, no matter how cute it was.
The puppy chewed up the leash ____ took a nap.
The power swelled until it was greater ____ the wizard had ever felt before.
The castle loomed larger ____ anything the boy had seen. He took a moment to gather his courage ____ stepped onto the drawbridge. His heart beat louder ____ the echo of his footsteps in the empty moat.
Write first, ____ edit.
Sorry if I made you as scared as that deer, thinking you’d have to post your answers publicly. No, this is just for helping yourself, not embarrassing anyone in public.
The horse was sure she could get more upvotes than any puppy, no matter how cute it was.
The puppy chewed up the leash then took a nap.
The power swelled until it was greater than the wizard had ever felt before.
The castle loomed larger than anything the boy had seen. He took a moment to gather his courage then stepped onto the drawbridge. His heart beat louder than the echo of his footsteps in the empty moat.
Write first, then edit.
I hope these simple explanations of when to choose then and when than helps make you more comfortable in your writing. Once you have an idea of when each is correct, it gets easier to use them correctly. Even seemingly minor errors like these can really impact a reader’s response to your work.
If you have questions, please ask me. Also feel free to post challenge sentences in the comments!