15 Common Title Case Mistakes (And How to Fix Them)

Title case looks simple enough: capitalize the important words in a headline. But the details trip up even experienced writers. Which prepositions get capitalized? What about the word after a colon? Is "is" a small word or not?

These aren't just academic questions. A headline with inconsistent capitalization looks sloppy. And if you're writing for a publication, getting title case wrong can mean rounds of edits or a rejected submission. The good news is that most title case errors fall into the same 15 patterns. Fix these, and your headlines will be clean every time.

Mistake 1: Lowercasing Short Verbs Like "Is," "Are," and "Be"

This is the single most common title case mistake. Writers see a short word and automatically leave it lowercase, not realizing it's a verb. But in every major style guide - AP, Chicago, APA, and MLA - verbs are always capitalized, regardless of length.

Words that get missed most often: is, are, be, am, was, were, do, has, had, go, it. They're short, they don't feel important, but they're verbs (or pronouns, in the case of "it") and they must be capitalized. Grammarly's style guide confirms this is the most common capitalization error they encounter.

Mistake 2: Forgetting to Capitalize the Last Word

Every style guide agrees: the first and last word of a title are always capitalized, even if they'd normally be lowercase. Writers sometimes end a title with a preposition or article and leave it lowercase out of habit.

This also applies to subtitles. If your title has a colon, the last word of the subtitle follows the same rule.

Mistake 3: Not Capitalizing After a Colon

Colons in titles create a common stumbling point. The rules differ by style guide, and many writers just guess.

On this one, the guides actually agree. The first word after a colon in a title is always capitalized. But writers who've internalized the "lowercase small words" rule sometimes forget this override.

Mistake 4: Getting Hyphenated Words Wrong

Hyphenated words are where title case gets genuinely tricky. Should you capitalize both parts? Only the first? This is one area where the style guides actually disagree.

The safest approach if you don't know which style you're using: capitalize both parts of the hyphenated word. Three of the four major guides prefer this. The exception is Chicago, which follows its own nuanced logic. For a deeper look, see our style comparison guide.

Mistake 5: Assuming All Long Words Are Capitalized

Here's where word length gets confusing. Many writers think: "If a word has four or more letters, capitalize it." But that's only sometimes true.

In AP style, prepositions with four or more letters are capitalized (so "With," "From," and "Between" are uppercase). But in MLA style, prepositions are always lowercase regardless of length - meaning "between," "through," and "without" all stay lowercase.

The fix: know which style guide you're following, and learn its specific rule for preposition length. Don't just count letters and guess.

Mistake 6: Capitalizing "To" in Infinitives

The word "to" causes confusion because it serves double duty. As a preposition ("went to the store"), it stays lowercase. As part of an infinitive ("How to Write"), it also stays lowercase. So far, so good - "to" is always lowercase in all four major styles.

The mistake happens when writers capitalize "to" because it feels like part of the verb. "How To Write" looks natural but is wrong in every style guide. The only exception: when "to" is the first or last word of a title.

Mistake 7: Confusing Subordinating and Coordinating Conjunctions

Coordinating conjunctions (and, but, or, nor, for, yet, so) are lowercase in title case. That's straightforward. But subordinating conjunctions - words like "because," "although," "since," "while," "unless" - are trickier.

Most style guides capitalize subordinating conjunctions because they function differently from the short coordinating ones. Chicago and APA both capitalize them. AP capitalizes them if they're four or more letters. The mistake is treating all conjunctions the same.

Mistake 8: Lowercasing Particles in Phrasal Verbs

Phrasal verbs are verbs that pair with a small word (called a particle) to create a new meaning: "give up," "break down," "turn off," "set up." The particle is essential to the meaning - "give up" means something completely different from "give." The Merriam-Webster guide to title case covers this distinction between particles and prepositions.

In title case, these particles should be capitalized because they're part of the verb. Most style guides agree on this, though it's one of the most commonly broken rules because the particles look like prepositions.

The trick is distinguishing particles from prepositions. Ask yourself: does the small word change the meaning of the verb? If removing it changes what the sentence means (set up vs. set), it's a particle and should be capitalized.

Mistake 9: Capitalizing Articles in the Middle of a Title

Articles (a, an, the) are lowercase in title case - unless they're the first or last word. This rule is consistent across all four major style guides. But writers sometimes capitalize "The" out of habit, especially when it feels like it's starting a new phrase.

The one exception: when "The" is part of a proper noun ("The New York Times"). In that case, it's capitalized because it's part of the name, not because of title case rules.

Mistake 10: Changing the Capitalization of Brand Names

Brand names and proper nouns have their own capitalization, and title case doesn't override it. "iPhone" stays "iPhone" even at the start of a title (though some guides recommend rewording to avoid starting with a lowercase letter). "eBay" stays "eBay." "macOS" stays "macOS."

Writers sometimes force brand names into standard title case patterns, capitalizing the first letter or removing intentional lowercasing. Resist that urge. The brand chose that styling for a reason, and altering it is technically incorrect.

Mistake 11: Not Knowing What to Do With "As"

"As" is one of those chameleon words that can function as a conjunction, preposition, or adverb depending on context. This makes it a consistent source of title case headaches.

In AP style, "as" is lowercase because it's three letters. In Chicago, it's lowercase when used as a preposition or conjunction. In APA, it's lowercase. The safest bet: leave "as" lowercase unless it's the first or last word. All four major guides agree on that approach in practice.

Mistake 12: Getting "Between," "Yet," and "So" Wrong

These three words cause outsize confusion because they sit at the intersection of length rules and part-of-speech rules.

"Between" is a preposition. In AP style (four-letter rule), it's capitalized. In MLA (all prepositions lowercase), it's not. Chicago keeps it lowercase. Know your style guide.

"Yet" and "so" are coordinating conjunctions - part of the FANBOYS group (for, and, nor, but, or, yet, so). Most style guides keep them lowercase. But "yet" can also be an adverb ("the yet-unfinished project"), in which case some guides capitalize it. Context matters.

When in doubt about any of these, our headline capitalization tool handles the logic for all four styles automatically.

Mistake 13: Mixing Up Style Guide Rules

This might be the most underappreciated mistake. A writer learns the AP four-letter rule for prepositions and then applies it to an APA paper. Or they follow Chicago's lowercase "between" while otherwise using AP rules. The result is a headline that follows no consistent system.

The style guides disagree on several specific points. Here are the biggest differences:

Pick one style guide. Stick to it. If your publication has a style sheet, follow it exactly. For a detailed comparison of all four systems, see our title case styles compared guide.

Mistake 14: Mishandling Scientific and Technical Terms

Technical writing adds another layer of complexity. Latin species names, chemical compounds, programming terms, and medical terminology all have their own capitalization conventions that title case shouldn't override. The APA's official capitalization guide specifically addresses how to handle specialized terms within title case headings.

For example, a species name like Escherichia coli keeps its specific epithet ("coli") lowercase even in a title. The chemical "pH" stays lowercase-uppercase. And programming language conventions (like "JavaScript" or "iOS") take priority over general title case rules. When in doubt, preserve the term's standard capitalization.

Mistake 15: Not Double-Checking With a Tool

Even after memorizing all these rules, the fastest writers still make title case mistakes. There are too many edge cases, too many words that function as multiple parts of speech, and too many places where style guides disagree.

That's why tools exist. Our free headline capitalization tool applies AP, Chicago, APA, and MLA rules instantly. Paste your headline, pick your style, and you'll see exactly which words should be capitalized. It's the fastest way to catch the kinds of mistakes we've covered in this guide.

Quick Reference Cheat Sheet

Clip this and keep it handy. These are the rules that apply across all four major style guides:

The bottom line: title case has more rules than most people realize, and the rules change depending on which style guide you follow. The 15 mistakes above cover roughly 90% of the errors writers make. Fix these patterns, and your headlines will look polished and professional every time. And when you're not sure, run it through a tool - there's no shame in double-checking.