Writing & StyleStyle guide

I.e. Punctuation

I.e. punctuation is a style-mechanics question rather than a different meaning of the abbreviation. This guide documents MLA treatment while keeping the recommendation scoped to that style system.

Quick answer

In MLA style, write i.e. with periods and follow it with a comma in the parenthetical use MLA recommends. Other editorial systems may format abbreviations differently, so follow the required house style.

Key details

Core IssuePunctuation around i.e. is governed by editorial style. MLA uses periods in the abbreviation and places a comma after it when the abbreviation is used in its recommended parenthetical context.
Phrase Rolepunctuating i.e. within edited prose
Registerformal to professional

Important caveats

Style Boundary

Do not turn one style manual’s punctuation rule into a universal grammar law; follow the required style guide, and spell out “that is” when clearer.

Further guidance

Comma

MLA places a comma after i.e. in the parenthetical constructions it recommends.

Form

In MLA style, the abbreviation is written “i.e.” with periods.

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. How do I use e.g. and i.e.? — MLA Style Center (opens in a new tab)Modern Language Association · Distinguishes e.g. (“for example”) from i.e. (“that is”) and documents MLA punctuation/style treatment

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