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A Chicago style heading organizes research papers, theses, and dissertations into clear structural divisions using an optional five-level hierarchy. Under The Chicago Manual of Style (18th edition, 2024) and Turabian guidelines, headings are distinguished by typeface, placement, and capitalization—ranging from centered bold headings in title case down to indented paragraph run-ins in sentence case.
Chicago Heading Levels at a Glance
While The Chicago Manual of Style provides flexibility for formatting subheadings, Chicago and Turabian outline a standard five-level hierarchy for manuscripts requiring formal division. Most academic papers require only two or three levels; extended dissertations or monographs may use all five.
| Level | Placement and Typeface | Capitalization | Terminal Punctuation | Recommended Application |
|---|---|---|---|---|
| Level 1 | Centered, boldface or italic type | Title case | No period | Major paper sections or chapter divisions |
| Level 2 | Centered, regular (roman) type | Title case | No period | Primary subsections within a Level 1 section |
| Level 3 | Flush left, boldface or italic type | Title case | No period | Second-tier subtopics under a Level 2 section |
| Level 4 | Flush left, regular (roman) type | Sentence case | No period | Minor subdivisions under a Level 3 section |
| Level 5 | Indented 0.5 in., run-in paragraph head (bold or italic) | Sentence case | Period at end | Discrete paragraph themes or sequential points |
In Chicago style, higher-level subheadings must stand out visually more than lower-level subheadings. Writers maintain visual subordination through typographic choices, positioning, and capitalization. For additional structural conventions across student papers, see our guide on Turabian formatting examples.
The 5-Level Hierarchy for Chicago Style Subheadings
Each heading level represents a distinct tier of subordination, ensuring readers immediately recognize how arguments fit together.
Level 1: Main Section Headings
Level 1 headings designate the highest division within a chapter or standalone paper. They are centered horizontally and formatted in boldface or italic type. Capitalization follows title case (formerly termed headline style in earlier editions), capitalizing major words. Do not place a period at the end of a Level 1 heading.
Level 2: Major Subsections
Level 2 subheadings break a Level 1 section into primary components. They remain centered on their own line in regular (roman) type using title case capitalization. Because Level 2 retains centered alignment but sheds bold formatting, it signals a logical subset of the preceding section.
Level 3: Component Topics
Level 3 subheadings move from the center to the left margin (flush left). They use boldface or italic type to maintain visual contrast against surrounding body text. Level 3 headings remain on their own line, use title case capitalization, and omit terminal punctuation.
Level 4: Detailed Subdivisions
Level 4 headings are positioned flush left in regular (roman) font. To signify deeper subordination, Chicago shifts Level 4 headings to sentence case capitalization: only the first word, proper nouns, and the first word following a colon are capitalized. Like Levels 1 through 3, Level 4 headings sit on their own line without a period.
Level 5: Run-In Paragraph Headings
Level 5 headings do not appear on an isolated line. Instead, they are indented half an inch (0.5 in.) from the left margin as the opening phrase of the paragraph. Formatted in boldface or italic type, Level 5 headings use sentence case capitalization and end with a period. Body text begins immediately after the period on the same line.
Reusable Template for Headings in Chicago Style
Researchers can adapt the structural template below when configuring word processor templates or LaTeX documents:
[Two blank lines before heading]
[LEVEL 1: CENTERED, BOLD, TITLE CASE]
[Double-spaced text begins with 0.5 in. indent...]
[LEVEL 2: CENTERED, REGULAR TYPE, TITLE CASE]
[Double-spaced text continues...]
[Level 3: Flush Left, Bold, Title Case]
[Double-spaced text continues...]
[Level 4: flush left, regular type, sentence case]
[Double-spaced text continues...]
Level 5 run-in heading in sentence case. Text begins immediately after the period...
Maintain parallel grammatical structure across headings of the same level. If your first Level 1 heading uses a noun phrase, subsequent Level 1 headings should also use noun phrases rather than switching to question forms.
Filled Example: Fictional Research Manuscript
The following fictional excerpt demonstrates how all five Chicago heading levels function in an academic research paper on medieval codicology:
Methods in Multispectral Codicology
Recent advances in optical imaging allow conservators to analyze erased palimpsests without destroying historical substrates. This investigation examines spectral recovery rates across twelfth-century European scriptoria.
Spectral Imaging Protocols
To establish baseline reflectance values, each parchment bifolium underwent narrow-band illumination across sixteen discrete wavelengths from 365 nm to 940 nm.
Calibration and Spectral Registration
Image registration required pixel alignment across alternating exposures. Spatial distortion was corrected using ceramic grid targets placed adjacent to manuscript leaves.
Fluorophore detection thresholds
Under ultraviolet stimulation, degradation products in iron-gall ink produce fluorescent emissions that diverge from the background matrix. Excitation filters isolated emissions between 420 nm and 480 nm to maximize contrast.
Secondary substrate interference. In three test folios, heavy gelatin sizing introduced diffuse autofluorescence. Principal component analysis separated the sizing spectral vector from residual carbon deposits, restoring legibility to scrubbed characters.
Notice that the Level 5 heading begins the paragraph directly, whereas Levels 1 through 4 occupy their own distinct lines. For guidance on coordinating headings with citations, see our overview of Chicago works cited formatting.
Capitalization and Typography Rules
Headings in Chicago style follow strict capitalization conventions established in The Chicago Manual of Style (18th edition, 2024, sections 2.65, 8.159, and 8.160):
- Title Case (Levels 1–3): Capitalize the first and last words, plus major words. Lowercase articles, coordinating conjunctions, and prepositions. For comparative analysis across citation styles, explore our guide on title case vs. sentence case rules.
- Sentence Case (Levels 4–5): Capitalize only the first word, proper nouns, and the first word following a colon. Other words remain lowercase.
- CMOS 18th Edition Flexibility (Section 2.65): Chicago 18th edition specifies that subheads may be formatted in either title case or sentence case, provided the choice is applied consistently across every heading within that level.
- Font Consistency: Headings use the same font family as body text (such as 12 pt Times New Roman). If font size indicates hierarchy, Level 1 headings may be set 1 to 2 points larger than body text.
- Vertical Spacing: Official Chicago guidelines specify leaving more vertical space before a heading than after it. In double-spaced manuscripts, leave two blank lines before the heading and one blank line between the heading and subsequent body text. Consecutive subheads require one blank line between them.
Manuscript Layout Checklist Before Submission
Before submitting a manuscript for peer review or dissertation deposit, audit your headings against this checklist:
- No Solitary Subheadings: Ensure you have at least two subheadings at every level within a section. If a topic does not require division into two or more parts, incorporate the content into the narrative without a heading.
- Prevent Orphan Headings: Never leave a subheading at the bottom of a page without at least two lines of body text underneath it. Enable “Keep with next” in your word processor.
- No Ending Periods on Display Heads: Levels 1, 2, 3, and 4 do not end with a period. Only Level 5 run-in headings conclude with a terminal period.
- Differentiate Running Headers from Section Headings: A Chicago style header (the running head in the top margin with the page number) serves pagination purposes. Do not confuse running heads with in-text subheadings.
- Section Breaks Without Headings: If dividing sections without titled headings, center three spaced asterisks (
* * *) on their own line with a blank line above and below.
For authors refining final draft mechanics, understanding structural editing versus formatting checks is critical; see our reference on copyediting vs proofreading.
Frequently Asked Questions About Chicago Style Headings
Does Chicago style require subheadings?
No. The Chicago Manual of Style does not mandate subheadings. They are optional aids. For short papers (under five pages), subheadings are usually unnecessary.
What is the difference between a Chicago style header and a heading?
A Chicago style header refers to the running head in the top page margin (author’s last name and page number). In contrast, a Chicago style heading is an in-text structural title (Levels 1 through 5) that introduces a section in the text body.
How many levels of headings should an academic paper use?
Most research papers and journal articles need only two or three levels of headings. Limiting subheadings prevents clutter. Four or five levels are generally reserved for book-length manuscripts and dissertations.
Can subheadings use sentence case in Chicago style?
Yes. While Levels 1 through 3 traditionally use title case in the standard five-level model, The Chicago Manual of Style (18th edition, section 2.65) allows authors to format subheads in sentence case, provided the choice is applied consistently across that level.
Sources
- University of Chicago Press. Turabian Tip Sheet 7: Sections and Subheads. Chicago: University of Chicago Press, 2018. https://www.chicagomanualofstyle.org/dam/jcr:134b5b19-bdc9-4d69-b4ad-0aa19fdc3730/Turabian-Tip-Sheet-7.pdf (read 2026-11-07).
- Saller, Carol. “How Do I Format Sections and Subheads in Turabian / Chicago Style?” CMOS Shop Talk, December 11, 2018. https://cmosshoptalk.com/2018/12/11/how-do-i-format-sections-and-subheads-in-turabian-chicago-style/ (read 2026-11-07).
- Purdue Online Writing Lab. “CMOS Formatting and Style Guide: General Format.” Purdue University, 2026. https://owl.purdue.edu/owl/research_and_citation/chicago_manual_17th_edition/cmos_formatting_and_style_guide/general_format.html (read 2026-11-07).
- University of Mary Washington Speaking and Writing Center. Chicago Style Guide: Title Page and Paper Formatting. Fredericksburg: UMW, October 2023. http://academics.umw.edu/swc/files/2023/10/Chicago-Style-Guide_-Title-Page-and-Paper-Formatting.pdf (read 2026-11-07).
- University of Chicago Press. The Chicago Manual of Style. 18th ed. Chicago: University of Chicago Press, 2024. Sections 2.65, 8.159, 8.160 (referenced via official style updates, read 2026-11-07).
