Don’t Let Headline-Style Capitalization Give You a Headache
Or: Breaking Down Chicago Manual of Style 8.159
In headline-style capitalization, Most Words Are Capitalized. It differs from sentence-style capitalization in which The first word and Proper Names are capitalized, but nothing else.
The Chicago Manual of Style sets out seven rules for headline-style capitalization of titles and subtitles. The first rule has two parenthetical “but see rule X” statements, so there are nine things to keep an eye on.
It’s a bit labyrinth. Let’s break it down. (Hey! If seven rules and nine things are too much, scroll to the bottom, where I’ve got a shortcut that STARTS with all caps.)

First and last word. You’re going to capitalize those suckers.
- But wait! Is your last word the second part of species name? Like sapiens in Homo sapiens?
- If no, stop reading now.
- If yes, those are always lowercased.
You are going to capitalize all other major words. These include:
- adjectives
- adverbs
- nouns
- pronouns
- verbs
Do you have a conjunction in your title? Okay, then, let’s take a look. Rule one says “some conjunctions” but also wants us to look at rule four. Skipping down to that rule, it tells us that specific coordinating conjunctions are lowercased. So! Check if your conjunctions are these words:
- and
- but
- for
- or
- nor
If your conjunctions aren’t in the list above, those are capitalized.
We’ve made it through rule one! Don’t worry, the next rule is easy.

We’ve got a clear directive to lowercase these specific articles:
- a
- an
- the
Easy enough. Moving on, rule three has two exceptions, so let’s break this one down.

First part. Prepositions, either short or long, are lowercased.
Yeah, so prepositions. They don’t lend themselves to a tidy and complete list. Here’s what Merriam-Webster has to say about them:
“A preposition is a word—and almost always a very small, very common word—that shows direction, location, or time, or that introduces an object. Prepositions are typically followed by an object, which can be a noun, a noun phrase, or a pronoun.”

So there won’t be any bulleted list here for prepositions. Maybe someone made you memorize a bunch of them? I hear there is a song? If so, you are good.
If not, you can look up a word in the dictionary and the definition will tell you if the word is a preposition. Or, you could throw your sentence into Parts-of-Speech.info and see which words are colored pink, which is the color they use to identify prepositions. And then maybe also look it up in the dictionary, because the POS-tagging is not 100% guaranteed.
Second part of rule three. Are your prepositions used adverbially or adjectivally? Cool, in that case, they are capitalized, not lowercased. Don’t know what they are talking about? Chicago gives these examples:
- up in Look Up
- down in Turn Down
- on in The On Button
- to in Come To
We only have to get through the third part of rule three and we’re done with this rule. The last four rules are much easier.
To see if third part of this rule applies to you, check your sentence for a Latin expression. Do you have one? If no, move along. If yes, check to see if the Latin expression is used adjectivally, or adverbially. If the answer is yes, you are going to capitalize the words in that expression.
I’m guessing this rule won’t be used 99.8% of the time, but if you are wondering what would be some examples of a Latin expression used adjectivally or adverbially Chicago uses:
- De Facto
- In Vitro

We did this one already, back in rule one! It says to lowercase the coordinating conjunctions: and, but, for, or, and nor!

Have you used to or an in your title or subtitle? They will be lowercased!
We already knew that to was lowercased because it’s a preposition, but even when it’s “part of an infinitive” it is still not capitalized.

Do you have any proper names in your title? Cool. Those will be capitalized.
But wait! Take one more look at your proper names. Do they have parts of them that would be lowercased normally? They will stay that way.
One example would be the best small character from the Coen Brothers’ movie Intolerable Cruelty: Heinz, the Baron, Krauss von Espy. That von stays lowercased. (As does that the due to rule four.)

We did this one already too! Back in rule one! It’s the species name one. The second part of the name is always lowercased. Always!
That was a lot! But now you know.
If you would like a handy one-page reference guide, shoot me a message and I’ll send it to you.
You can also use the following technique where you start with everything capitalized:
Capitalize everything.
Look for and lowercase:
- a
- an
- as
- and
- but
- for
- nor
- or
- the
- to
Look for and lowercase:
- prepositions
- but not when used adverbially
- but not when used adjectivally
- but not when they are part of a Latin expression used adjectivally or adverbially
Look for and lowercase proper nouns normally lowercased:
- de
- von
Look for and lowercase the second part of species names.