APA vs MLA vs Chicago: Quick Matrix
Someone's told you to "use APA" or "put it in Chicago," and you just want to know which way each one jumps on the handful of points people actually argue about. Here's that, at a glance — where the three guides agree, where they split, and which article to read if you want the rule itself rather than the verdict. Every row points home; nothing here re-teaches.
A quick word before the grid: all three are American academic and publishing systems. They assume US spelling, US quotation punctuation, and US date order unless an editor tells you otherwise. That's not a flaw — it's just their remit. For UK house style, see Oxford / Hart's Rules (piece 14) rather than expecting these three to switch sides for you.
| Contested point | APA (7th) | MLA (9th) | Chicago (17th / CMOS) | Status | Home |
|---|---|---|---|---|---|
| Serial (Oxford) comma | Required in a series of three or more | Required in a series of three or more | Strongly recommended in a series of three or more | Fixed — all three want it | P6 · Commas |
| Title capitalisation | Title case for work titles in running text and for periodical names; sentence case for article, chapter and web-page titles in the reference list | Title case (headline style) for titles in the works-cited list and in the text | Title case (headline style) for English titles in notes, bibliography and text | Variant — all lean title case, but APA switches to sentence case for article titles in references | P7 · Capitalisation |
| Quotation-mark style | Double marks primary, single for nested; commas and full stops [US: periods] inside the closing mark | Double primary, single nested; commas and full stops inside the closing mark | Double primary, single nested; commas and full stops inside in US editions — CMOS notes British placement as an editorial alternative | Fixed as US style for APA & MLA; tendency for Chicago, which permits the British variant | P6 · Quotation marks |
| Number treatment | Numerals for 10 and above, words below 10 (with standard exceptions: start of a sentence, statistics, measurements) | Words for numbers expressible in one or two words; numerals for the rest | Non-technical prose: words for zero through one hundred. Technical/scientific: numerals more freely. Words at the start of a sentence either way | Variant — three different thresholds | P8 · Word choice & number style |
Reading the Status column. Fixed means the guide is clear and consistent. Tendency means a strong default with narrow room for editorial choice. Variant means the three genuinely diverge, or one guide runs more than one internal rule.
Where UK practice differs
The three guides above are US-facing, so a UK writer working to a British house style will see daylight on some of these. Shown honestly — a blank would be an invented divergence, and there isn't one worth faking here.
| Point | UK house tendency | US (APA / MLA / CMOS default) | Status |
|---|---|---|---|
| Serial comma | Often omitted unless clarity demands it (Hart's) | Required or effectively required | Variant |
| Quotation marks | Single often primary; punctuation set by sense (logical style) | Double primary; commas and full stops [US: periods] inside | Fixed difference in default |
| Number style | House-dependent; many UK presses spell out more than APA's "10 and above" | Per the rows above | Tendency + house variation |
For the spelling systems these guides quietly assume (-ise/-ize, -our/-or), see P8 · Spelling variants.
The short version
- All three want the serial comma. That one's not contested between them — P6.
- The real split among the three is title capitalisation in reference lists (APA sentence case; MLA and Chicago title case) and where the numbers threshold sits — P7, P8.
- Quotation style across all three is American by default: doubles first, commas and full stops inside — P6.
- For UK work, reach for Oxford / Hart's (piece 14); for the fuller map of who disagrees with whom, Contested points (piece 15).
Roger Fielding — Bristol. This page finds the rule; the Pillar it links to teaches it. If a style guide's making you feel small, that's the guide's problem, not yours.