Writing & StyleRule guide

Multiword Prepositions in Title Case

Multiword prepositions such as “according to,” “because of,” “instead of,” “out of,” and “up to” should not be handled by a single crude small-word list. Different style systems analyze components differently, and some phrases contain words that can change grammatical role.

Reviewed2026-09-28Evidence6 sourcesSectionWriting & Style

Quick answer

Recognize the phrase, then apply the relevant style’s component rules. Do not assume that every word in a multiword preposition must receive the same capitalization.

Key details

Reviewed Phrasesaccording to, because of, due to, instead of, out of, up to

Rule Familymultiword-preposition-title-case

Style-by-style guidance

Chicago 18

Chicago 18 treats title-case words component by component and now capitalizes prepositions of five letters or more; its current Q&A gives “The Gospel According to Matthew.”

Important caveats

Automation Policy

A recognized phrase span can add context and trace information; it is never allowed to convert an unresolved token from unsafe to safe on recognition alone.

Mla Boundary

MLA has public guidance specifically addressing two-word prepositions, but the public page is edition-scoped. This guide therefore keeps the current MLA named converter disabled until the current rule set is completely encoded.

Further guidance

Practical Application

Identify the full phrase and then apply the selected title-case style to each component by grammatical role and the style’s own rules. Do not hard-code every word in phrases such as “according to” or “because of” to the same capitalization behavior.

Reader Check

Have you parsed the phrase in context and checked the actual style rule, rather than treating it as one indivisible small-word token?

Why Phrase Recognition Matters

Recognition prevents a converter from treating adjacent words as unrelated, but it is only one layer of the decision.

Worked Example

In an automated title-case system, “according to” should be evaluated component by component under the target style; a blanket rule that lowercases every word in every multiword preposition will mis-handle edge cases and role changes.

Sources and evidence

Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.

Title case capitalization (opens in a new tab)American Psychological Association · APA title-case rules
What's New in the 18th Edition (opens in a new tab)The Chicago Manual of Style / University of Chicago Press · Chicago 18 title-case terminology and five-letter-preposition change
Headlines and Titles of Works — Chicago Q&A (opens in a new tab)The Chicago Manual of Style / University of Chicago Press · Chicago title-case rules and current-edition updates
How should I capitalize the title of a handout? (opens in a new tab)MLA Style Center / Modern Language Association · MLA title-style capitalization
In MLA style, should any part of a two-word preposition be capitalized in a title? (opens in a new tab)MLA Style Center / Modern Language Association · MLA editorial guidance on internal prepositions in titles
Headlines and Titles of Works — “as well as” and “as” (opens in a new tab)The Chicago Manual of Style / University of Chicago Press · Chicago treatment of “as” in any grammatical function

Related guides

Writing & Style

Prepositions in Title Case

Prepositions are one of the clearest places where title styles diverge. APA uses a four-letter major-word threshold, Chicago 18 capitalizes prepositions of five letters or more, and MLA editorial guidance generally lowercases internal prepositions regardless of length.

Writing & Style

How to Capitalize “According To” in a Title

“according to” is a multiword expression whose title-case result depends on both style and how that style treats the words inside a phrase. Treat the expression as a phrase span while still applying the chosen style’s rule to each component rather than treating the phrase as one indivisible token.

Writing & Style

How to Capitalize “Because Of” in a Title

“because of” is a multiword expression whose title-case result depends on both style and how that style treats the words inside a phrase. Treat the expression as a phrase span while still applying the chosen style’s rule to each component rather than treating the phrase as one indivisible token.

Writing & Style

How to Capitalize “Due To” in a Title

“due to” is a multiword expression whose title-case result depends on both style and how that style treats the words inside a phrase. Treat the expression as a phrase span while still applying the chosen style’s rule to each component rather than treating the phrase as one indivisible token.

Writing & Style

How to Capitalize “Instead Of” in a Title

“instead of” is a multiword expression whose title-case result depends on both style and how that style treats the words inside a phrase. Treat the expression as a phrase span while still applying the chosen style’s rule to each component rather than treating the phrase as one indivisible token.

Writing & Style

How to Capitalize “Out Of” in a Title

“out of” is a multiword expression whose title-case result depends on both style and how that style treats the words inside a phrase. Treat the expression as a phrase span while still applying the chosen style’s rule to each component rather than treating the phrase as one indivisible token.

Writing & Style

How to Capitalize “Up To” in a Title

“up to” is a multiword expression whose title-case result depends on both style and how that style treats the words inside a phrase. Treat the expression as a phrase span while still applying the chosen style’s rule to each component rather than treating the phrase as one indivisible token.

Writing & Style

Hyphenated Compounds in Title Case

Hyphenated compounds cannot be capitalized safely with one universal “capitalize everything after a hyphen” rule. APA explicitly capitalizes the second part of hyphenated major words, while Chicago 18 changed its prefix-compound treatment and still applies grammatical title-case rules to individual elements.

Explore the topic

Capitalization Title Case Style Guides