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Grammar

Capitalization Rules — A Complete Guide + Examples

Learn how to capitalize text properly. Get insight with specific capitalization examples, so you can write clearly and professionally.

The basics of English capitalization rules get covered early in language learning and are built upon over time because there are so many. 

Some capitalization conventions come fairly intuitively because we use them frequently—for instance, the capital letter at the beginning of a sentence. 

Other capitalization rules can be more confounding, especially in situations we encounter less frequently. 

For professional writers and marketers, some capitalization rules may vary, depending on what editorial style guide their organization or client follows. 

Learn about capitalization in English grammar and best practices for capitalizing names, places, and titles properly.

Then, conveniently review your text to make sure you are capitalizing correctly with the Originality.ai Grammar Checker.

Why Is Capitalization Used in English Grammar?

Anyone who has received a text message in ALL CAPS knows that capitalization draws a reader’s attention. 

When used correctly and according to the rules of grammar, a capital letter is a signal to a reader and places emphasis on a word for a reason. 

Capitalize the First Letter in Every Sentence

Capitalization of a sentence’s first word is a foundational rule of grammar. Whether it is a noun, adjective, or verb, the first letter of a sentence is capitalized.

Examples:

  • Mary always plants a bright flower garden.
  • Pink is the color of Mary’s flowers. 
  • Is it just me, or are the flowers blooming earlier this year?

Do not capitalize the first word after a colon in a sentence. Unless a proper noun follows the colon, there is no need to capitalize the first word.

Examples:

  • Sharon asked for two things: peace and quiet.
  • Two people came to the party: Sharon and Joe.

Proper Nouns Always Begin with a Capital Letter

A capital letter is used to indicate that a noun is proper and specific rather than common. Here is a quick refresher on those grammar terms:

  • Noun: A noun names a person, place, or thing that is concrete or abstract.
    • Examples: boy, Jim, country, happiness, freedom, Spain, mountain, New York
  • Common noun: A non-specific or general person, place, or thing.
    • Examples: boy, country, happiness, freedom, mountain
  • Proper noun: A specific person, place, or thing.
    • Examples: Jim, Spain, New York

It’s easy to remember to capitalize the names of people, as we are taught to capitalize our own names when we start to write. 

In addition to names, other categories of proper nouns are always capitalized. 

Cities, states, countries, continents, planets, landmarks, and languages

The formal names of specific places and their languages are always capitalized, no matter where they appear in a sentence.

Examples:

  • French is my language because I live in France.
  • I am French and French food is my favorite.
  • The continent of North America includes countries like Canada and the United States.
  • My favorite city in the United States is Chicago.
  • Italian coffee makes my heart sing.
  • The Eiffel Tower is a French landmark.
  • Lake Michigan touches Illinois, Indiana, Michigan, and Wisconsin.
  • Earth is our planet.

Note that in the examples above these common nouns above are not capitalized, even when they appear next to the proper noun: language, food, countries, continent, city, coffee, landmark, and planet.

Similarly, the specific and proper names of streets, rivers, mountain ranges, monuments, religions, and deities are also capitalized. 

Geographical regions

Regions of a country are capitalized. However, the points on a compass are not. 

The distinction here is that when referring to the name for a specific geographical region, capitalize the name. When referring to general compass directions, do not capitalize. 

Examples:

  • Lake Michigan is in the Midwest.
  • Illinois borders the southwest shores of Lake Michigan.
  • We took a trip to the West Coast.
  • I think the shop is on the east side of the street. 
  • She lives in New York’s Lower East Side.

It can sometimes be tricky to know whether a part of a city is a proper, widely recognized name or simply a compass direction, consult the dictionary or style guide used by your organization. 

Company names and trademarks

Names of companies are proper names, so each word in the company name begins with a capital letter.

Examples of company names:

  • Alphabet Inc.
  • Meta Platforms, Inc.

Examples of trademarks:

  • Thermos
  • Styrofoam
  • Photoshop

Sometimes there are exceptions

When a name begins with a lowercase letter, like iPhone, it can be tricky to know how to handle this at the beginning of a sentence. 

So, in certain instances like with ‘iPhone’ the most common practice is to maintain the company’s preferred format, in which case, if ‘iPhone’ is at the beginning of the sentence it may begin with a lowercase letter.

Always refer to your organization’s style guide to confirm.

Title of honor and rank with a proper name

When a professional title or rank precedes a person’s name, it is capitalized because it refers to that specific person. 

If the title or rank does not precede a person’s name, it is usually lowercase.

Examples: 

  • Governor Smith appeared in public today.
  • The governor appeared in public today.
  • Professor Smith gave an excellent lecture.
  • The professor gave an excellent lecture.

Similarly, the title for family members is capitalized when it directly precedes a name but not when it doesn’t precede a name.

Examples: 

  • Auntie Angie is my favorite aunt.
  • My favorite aunt’s name is Angie.

Historical events, periods, and documents

Specific historical eras and events are capitalized. General time periods, such as centuries and decades, are not capitalized. The names of important historical documents are also capitalized.

Examples: 

  • Ice Age
  • World War II
  • Roaring Twenties

The proper names of specific historical documents are capitalized. Words that refer to general, unspecific documents are not.

Examples:

  • U.S. Constitution
  • The country has a written constitution.
  • Magna Carta
  • She drew up a charter of rights.
  • United States Bill of Rights
  • The bill is up for consideration.

Holidays, days of the week, and months of the year

The days of the week, months of the year, and specific holidays are always capitalized; the names of the seasons are not.

Examples:

  • Her birthday is on Monday, July 26.
  • Her birthday is in the summer.
  • Thanksgiving is in November.

The titles of books, films, and works of art

The first letter of every word in the titles of publications and works of art is capitalized.

Examples:

  • Huckleberry Finn
  • Shakespeare’s All’s Well That Ends Well
  • The Godfather Part II
  • Mona Lisa
  • The New York Times

Other treatments for a title’s appearance, such as whether it appears in italics or quotation marks, may vary depending on what editorial style guide your organization follows. 

Some specific abbreviations

Some abbreviations are always capitalized. For example:

  • U.S. states: IL, NY, CA
  • Time periods: AD, BC, BCE, CE
  • Academic and professional degrees: BA, MA, PhD, CPA

Final Thoughts

In many cases, capitalization may come naturally to you as you write. But there is no doubt that some rules can get tricky depending on what words you encounter in your writing. 

Professional writers and marketers should check their organization’s editorial style guide as a reference.

Conveniently review your content with the Originality.ai Grammar Checker to ensure your content is capitalized correctly.

Learn more about grammar and spelling best practices in our top guides:

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