Abbreviations and Acronyms

General Rules:

  • In general, do not use abbreviations or acronyms on first reference.
    • Exceptions: The most common abbreviations and acronyms: AFC, AFL-CIO, CEO, CIA, CNN, CPR, DNA, DUI/DWI, DVD, FBI, FM, GPA, IBM, Interpol, LPGA, LSD, NASCAR, NATO, NBA, NCAA, NFC, NFL, NHL, NPR, PGA, PTA, RAM, UFO, UNESCO, UNICEF, USGA, VCR
  • Do not place an abbreviation or acronym in parentheses after the first reference.
  • Only use abbreviations and acronyms on second reference if readers would easily recognize them. Allow the context to determine whether or not the shortened form is appropriate.
    • Correct: The Centers for Disease Control and Prevention recommends yearly vaccinations. According to the CDC, vaccines save lives.
    • Incorrect: The Global Alliance for Vaccines and Immunizations increases access to vaccines in developing nations. GAVI has funded immunizations for over 370 million children.
  • Commonly used acronyms/abbreviations acceptable on second reference: ACLU, AMA, ASPCA, CBC, CDC, DNS, DVR, DEA, EPA, EEOC, FAA, FCC, FDIC, FEMA, FHA, the Fed, GOP, IM, IUD, IT, MRSA, NEA, NLRB, NOW, TVA, U.N., ICE, WMD, WHO

Caps and Periods

Rule: Most two-letter abbreviations require periods.

  • Correct: A.D., B.C., U.S., U.N. (Exceptions: AP, GI, ID, EU)
  • Incorrect: AD, BC, US, UN

Rule: Use all caps and no periods when letters in a longer abbreviation are spelled out individually.

  • Correct: ABC, CNN, FBI, IBM, USA
  • Incorrect: A.B.C., C.N.N., F.B.I., I.B.M., U.S.A.
Rule: For acronyms of more than five letters, capitalize the first letter. Use lowercase for remaining letters. Do not use periods.

  • Correct: Nasdaq
  • Incorrect: NASDAQ
Rule: Use only one period (.) when an abbreviation or acronym ends a sentence.

Days of the Week

Rule: Never abbreviate days of the week unless they are used in tabular format.

  • Correct: The staff wears jerseys on Fridays.
  • Incorrect: The games usually fall on Tues. and Thurs.

Months of the Year

Rule: Use abbreviations when months of the year are listed with a specific date (“month, day” or “month, day, year”) for these months: Jan., Feb., Aug., Sept., Oct., Nov. and Dec.

Rule: Spell out these months: March, April, May, June and July.

  • Correct: The merger is to take place on Dec. 15, 2012.
  • Correct: March 13, 2013, is the deadline.
  • Incorrect: The event falls on December 12, 2012.
  • Incorrect: The company formed on Mar. 17, 2011.

Rule: When months are listed alone or with the year only, spell out all months of the year.

  • Correct: August is the best time to go camping.
  • Incorrect: By Sept., the nighttime temperatures are too low.

Rule: When referring to only a month and a year, do not set off the year with commas.

  • Example: February 1989 holds the record for snowiest month in history.

Rule: When referring to a month, day and year, set off the year with commas.

  • Example: Feb. 24, 1989, had the most amount of snow that month.

United States

Rule: Abbreviate United States when used as an adjective. Use periods.

  • Correct: The U.S. population continues to grow.
  • Incorrect: United States security is stronger than ever.

Rule: Spell out United States when used as a noun.

  • Correct: In the United States, people expect immediate gratification.
  • Incorrect: The corporate office is based in the U.S.

State Abbreviations

Rule: Spell out the names of the 50 U.S. states, whether standing alone or in conjunction with a city, town, village or military base.

  • Correct: The event is in Lansing, Michigan.
  • Incorrect: The office moved to Lansing, Mich., two months ago.

Rule: Place one comma between the city and the state name, and another comma after the state name, unless ending a sentence.

  • Example: She traveled from St. Louis, Missouri, to Denver, Colorado.

Rule: Use two-letter, all-cap postal-code abbreviations only when giving a full address with ZIP code.

  • Correct: The main office is at 332 S. Center St., Green Bay, WI, 54301.
  • Incorrect: The stadium is in Green Bay, WI.

Rule: Use the word “state” to distinguish between New York state and New York City when necessary.

Units of Measurement

Rule: Do not use abbreviations for units of measurement; spell them out instead.

Rule: Always use figures before units of measurement.

  • Correct: The flood left 3 feet of water in the basement.
  • Incorrect: It snowed 8 in. last night.
  • Incorrect: It snowed eight inches last night.

Rule: Use an apostrophe to indicate feet and quotation marks to indicate inches (5’3”) only in very technical contexts.


Academic Degrees

Rule: If mention of degrees is necessary to establish a person’s credentials, avoid abbreviations, and use phrases such as “Mary Snow, who has a doctorate in English literature.”

Rule: Use abbreviations such as B.A., M.A., and Ph.D. only when the need to identify many individuals by degree on first reference would make the preferred form cumbersome. Use these abbreviations only after a full name — never after just a last name.

  • Correct: Jane Smith, B.A., Terry Hughes, Ph.D., and Jenny Jones, M.A., agree that William Shakespeare was indeed the author of the works attributed to him.
  • Incorrect: Jane Smith, who has a bachelor’s degree in English literature, Terry Hughes, who has a doctorate in British literature, and Jenny Jones, who has a master’s degree in Shakespeare Studies, agree that William Shakespeare was indeed the author of the works attributed to him.

Rule: When used after a name, an academic abbreviation is set off by commas.

  • Example: Brittany Dalton, Ph.D., spoke at the university Friday.

Rule: Use an apostrophe for “bachelor’s degree,” “master’s degree,” etc.

Rule: Do not use an apostrophe for “Bachelor of Science,” “Master of Arts,” etc.

Rule: “Associate degree” (no possessive), not “associate’s degree”

I.e. vs. E.g.

Rule: In general, avoid using “i.e.” and “e.g.” unless absolutely necessary.

Rule: “I.e.” means “that is to say” and is always followed by a comma.

Rule: “E.g.” means “for example” and is always followed by a comma.


Etc. vs. Et al.


Rule: In general, avoid using “etc.” and “et al.” unless absolutely necessary.

Rule: “Etc.” means “and so forth” and should be used when referring to things.

Rule: “Et al.” means “and others” and should be used when referring to people.