This site addresses a number of punctuation issues, including punctuating with quotation marks, choosing between parentheses and dashes, using the semicolon and colon, and deciding when to use the Oxford comma.  Here we are focusing specifically on punctuating with expressions enclosed in parentheses.

Let’s Start with a Quiz

Which sentences are punctuated appropriately?

  1. The meeting will convene at the Hilton (Riverside, not Hightower).
  2. Despite having recently hired two new employees (Johnson and Carlisle,) the director attended the job fair.
  3. The results indicate a preference among employees for flexible holidays, (see appendix for survey data) but a new policy has not yet been implemented.
  4. The results indicate a preference among employees for flexible holidays. (See appendix for survey data.)
  5. The results indicate a preference among employees for flexible holidays (survey data in appendix.)

Commas and Periods Typically Belong with Their Clauses

Sentence 1 is correct: the period goes outside the parenthetical expression to end the entire sentence.

In sentence 2, the comma goes outside the closing parenthesis to signify that the parenthetical phrase belongs with the introductory clause:

Despite having recently hired two new employees (Johnson and Carlisle), the director attended the job fair.

Sentence 3 needs a comma before but because it joins two independent clauses. And since the parenthetical expression happens to come at that juncture, the comma should go after the closing parenthesis:

The results indicate a preference among employees for flexible holidays (see appendix for survey data), but a new policy has not yet been implemented.

What If Parentheses Enclose a Sentence within a Sentence?

When parentheses enclose a complete sentence, the punctuation depends on where it appears in the larger sentence.

The expression “see appendix for survey data” in sentence 3 is a complete sentence, but we do not treat it as such because it’s cocooned within another complete sentence. Therefore, we neither capitalize the first letter of “see” nor include a period after “data.”

Punctuating with Parentheses at the End of a Sentence

The parenthetical expression in sentence 4 is also a complete sentence, and it is correctly punctuated as such. Since it is entirely separate from the previous sentence, it must begin with a capital letter and end with its own appropriate punctuation mark placed inside the closing parenthesis.

When, however, an expression does not constitute a complete sentence but appears at the end of an independent clause, as with sentence 5, we punctuate after the closing parenthesis:

The results indicate a preference among employees for flexible holidays (survey data in appendix).

Punctuating with Static Parentheses

Static parentheses are not subject to the punctuation rules we have discussed so far because they don’t enclose words or phrases; they are used to enclose the letters or numbers delineating listed items, area codes, abbreviations, and so forth:

Leave one line of space between (1) the address and the greeting, (2) the greeting and the body of the letter, and (3) the body and the closing.

Call us at (555) 123-4567 to (a) request a catalog or (b) inquire about returns.

The North Atlantic Treaty Organization (NATO) includes many members of the EU (European Union).

And remember: parentheses almost always travel in pairs. Unless your style manual dictates otherwise, always employ both opening and closing parentheses (even in vertical lists).

TEST YOURSELF

  1. The employee’s Social Security number, (or if it is unavailable, the ID number in the database) must be entered for each name.
  2. The chair of the board has made recommendations (report to be published next week.)
  3. The chair of the board has made recommendations (the report will be published next week.)
  4. According to an article in a local newspaper (not the one owned by Knight Ridder), one-third of this state’s colleges and universities exceeded their performance-funding measures this year.

ANSWERS

  1. The employee’s Social Security number (or if it is unavailable, the ID number in the database) must be entered for each name. [Note that we need no punctuation this case.]
  2. The chair of the board has made recommendations (report to be published next week).
  3. The chair of the board has made recommendations. (The report will be published next week.)
  4. CORRECT

Copyright 2001 Get It Write. Revised 2022.