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Is “Until” or “Till” Capitalized in a Title?

Until and till can both function as prepositions or subordinating conjunctions. APA capitalizes both because each has at least four letters. Chicago 18 capitalizes until, while till needs grammatical-role analysis because a four-letter preposition is lowercased but a subordinating conjunction is capitalized. MLA likewise depends on whether the word is functioning as a preposition or a subordinating conjunction.

ReviewedEvidence7 sourcesSectionWriting & Style
Quick answer

APA: capitalize Until and Till. Chicago 18: capitalize Until; for Till, capitalize a subordinating conjunction but lowercase an internal preposition. MLA: capitalize a subordinating conjunction but lowercase an internal preposition.

Key details

APA 7Capitalize both internally.
Chicago 18Capitalize Until; Till is POS-sensitive.
MLA 9POS-sensitive: lowercase as preposition, capitalize as subordinating conjunction.
TermsUntil, Till
Word Classpreposition or subordinating conjunction

Important caveats

Automation boundary

The reviewed rule set treats Chicago/MLA “till” as POS-sensitive and fails closed when the role cannot be established.

Grammar Boundary

Cambridge identifies until/till as both prepositions and subordinating conjunctions. MLA’s grammar guidance likewise uses until in both roles.

Further guidance

Quick rule

Until is five letters and is capitalized internally in APA and Chicago 18.

Till is four letters: APA capitalizes it by the four-letter rule; Chicago and MLA need its grammatical role.

Register note

Cambridge describes till and ’til as more informal than until; that register distinction does not itself decide title capitalization.

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.

  1. Title case capitalization (opens in a new tab)American Psychological Association · APA title-case rules
  2. 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
  3. 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
  4. How should I capitalize the title of a handout? (opens in a new tab)MLA Style Center / Modern Language Association · MLA title-style capitalization
  5. 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
  6. Until — English Grammar Today (opens in a new tab)Cambridge University Press · Preposition/conjunction evidence for until and till
  7. Conjunctions (opens in a new tab)MLA Style Center · Coordinating versus subordinating conjunctions and examples including until/since

Related guides

Writing & Style

APA Title Case

APA title case capitalizes the first word, the first word of a subtitle, major words, and words of four letters or more while keeping short minor words lowercase in ordinary mid-title positions.

Writing & Style

Chicago Title Case (18th Edition)

Chicago 18 uses title case for titles of works and changed a long-standing rule: prepositions of five letters or more are now capitalized. Shorter prepositions generally remain lowercase internally, while first and last words are capitalized and “to” remains lowercase as an infinitive marker in ordinary mid-title use.

Writing & Style

MLA Title Case

MLA 9 describes title style as capitalizing the first word, last word, and all principal words. MLA’s public Style Center also documents the traditional lowercase treatment of internal prepositions, but its detailed preposition article is edition-labeled for MLA 8, so this engine does not yet treat the full MLA 9 converter profile as complete.

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.

Explore the topic

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