Complementary or Complimentary: Which Spelling Is Correct?
Have you ever written “complimentary breakfast” and wondered if it should be “complementary breakfast”? You are not alone.
Complementary or complimentary is a common English spelling question because the two words look and sound almost the same. Yet they have different meanings.
Complementary means that two things work well together, complete each other, or add something useful. For example, “The two colors are complementary.” Complimentary usually means giving praise or approval.
It can also mean something is free, such as “The hotel offers complimentary breakfast.”
People search for this keyword when writing emails, reports, websites, schoolwork, business copy, and social media posts. One wrong letter can change the meaning of a sentence.
This guide gives you a quick answer first, then explains the history, spelling, common mistakes, real-world examples, and usage advice.
It also shows why complementary and complimentary are confused and how to choose the right word every time.
Complementary or Complimentary Quick Answer
The correct word depends on what you mean.
| Word | Meaning | Example |
| Complementary | Things that complete or improve each other | “The two skills are complementary.” |
| Complimentary | Expressing praise | “She made complimentary comments.” |
| Complimentary | Given free as a courtesy | “Guests receive complimentary drinks.” |
Easy memory trick
Think:
- Complementary = complete → something completes or works well with something else.
- Complimentary = compliment → praise or something given free.
For example:
The designer chose complementary colors.
The client was complimentary about the designer’s work.
The hotel offers complimentary breakfast.
Both spellings are correct. They simply have different meanings.
The Origin of Complementary or Complimentary
The two words have a shared history, which helps explain their similar spelling.
Complement comes from Latin complementum, meaning something that fills up or completes. It is related to the Latin verb complere, meaning “to fill” or “to complete.” The word entered English through Old French.
Complementary developed from complement + -ary. Early uses date to the 1620s. The modern idea of things “mutually completing” each other appeared later, with recorded use from the late 18th century.
The word also developed technical meanings, such as complementary colors.
Compliment took a different path. It is related to the same older family of words but passed through French, Italian, and Spanish. In English, the spelling shifted toward compliment after about the mid-17th century.
Complimentary comes from compliment + -ary. It originally meant something intended to express a compliment. Its meaning later expanded to include things given free as a courtesy.
So, the spelling difference is not random. The words developed from closely related roots but became separate words with different meanings.
British English vs American English Spelling
Here is an important point: British English and American English use the same spellings for these two words.
There is no standard British/American spelling change such as colour/color.
| Meaning | British English | American English |
| Completes or works well with something | complementary | complementary |
| Expressing praise | complimentary | complimentary |
| Given free | complimentary | complimentary |
| Works well together | “complementary skills” | “complementary skills” |
| Free service | “complimentary breakfast” | “complimentary breakfast” |
Oxford and Cambridge list the same two forms and meanings for English learners in both British and American contexts.
The difference is therefore meaning, not regional spelling.
For example, a British writer and an American writer would both write:
- “The hotel provides complimentary breakfast.”
- “Their skills are complementary.”
Australian English also follows the same distinction. The United States Studies Centre’s style guide, for example, defines complementary as completing or supplementing and complimentary as free or flattering.
Which Spelling Should You Use?
Use the spelling that matches your meaning.
For US readers
Use:
- complementary for things that work together
- complimentary for praise
- complimentary for free products or services
Example:
The two software tools provide complementary features.
We received complimentary tickets.
For UK and Commonwealth readers
Use exactly the same distinction.
The colors are complementary.
The manager was complimentary about our work.
Guests receive complimentary tea and coffee.
For a global audience
Do not change the spelling to suit the country. Instead, focus on the meaning.
If your sentence means “works well with”, choose complementary.
If it means “praising” or “free”, choose complimentary.
This rule works across major varieties of English.
Common Mistakes with Complementary or Complimentary
These words are often confused because they sound alike and share much of the same spelling.
Mistake 1: “Complimentary colors”
Incorrect:
These are complimentary colors.
Correct:
These are complementary colors.
Colors that work as contrasting pairs are called complementary colors.
Mistake 2: “Complementary breakfast”
Incorrect:
The hotel offers complementary breakfast.
Correct:
The hotel offers complimentary breakfast.
Here, breakfast is free, so complimentary is correct.
Mistake 3: “Complementary remarks”
Incorrect:
She made complementary remarks about my work.
Correct:
She made complimentary remarks about my work.
The remarks express praise, so use complimentary.
Mistake 4: “Complimentary skills”
Incorrect when you mean that skills work well together:
The team has complimentary skills.
Correct:
The team has complementary skills.
Cambridge uses “complementary skills” for different skills that are useful together.
Mistake 5: Confusing the verbs
Remember the related verbs:
- complement = complete or improve something
- compliment = praise someone
Example:
The sauce complements the dish.
She complimented the chef.
Complementary or Complimentary in Everyday Examples
The best way to learn these words is to see them in real situations.
In emails
Complementary:
Our teams have complementary skills, so I believe we can work well together.
Complimentary:
Thank you for your complimentary feedback about our service.
Complimentary = free:
We are pleased to offer you a complimentary consultation.
In news writing
Complementary:
The two policies take complementary approaches to the problem.
Complimentary:
The actor received complimentary reviews for the performance.
In social media
Complementary:
These colors look great together. They are perfectly complementary.
Complimentary:
Thanks for the complimentary comments on our new product!
In formal writing
Complementary:
The researchers used two complementary methods.
Complimentary:
The report included complimentary comments about the team’s performance.
Complimentary = free:
Visitors will receive complimentary materials at registration.
These uses match standard dictionary definitions and professional style guidance.
Complementary or Complimentary Comparison Table
| Feature | Complementary | Complimentary |
| Basic meaning | Completes or works well with something | Gives praise or is provided free |
| Related word | Complement | Compliment |
| Memory word | Complete | Compliment |
| Common phrase | complementary skills | complimentary breakfast |
| Another common phrase | complementary colors | complimentary remarks |
| Business use | complementary products | complimentary service |
| Describes praise? | No | Yes |
| Means free? | No | Yes |
| Means “works well together”? | Yes | No |
Complementary or Complimentary Google Trends & Usage Data
Search interest in these words is affected by meaning and context. Google Trends measures relative search interest, not a fixed number of searches, so results can change by country, date range, and search category.
The two terms also appear in very different contexts.
Complementary is common in searches and content about:
- colors
- skills
- products
- business strategy
- mathematics
- science
- complementary medicine
- education
Cambridge, for example, lists uses such as complementary skills, complementary colors, complementary medicine, and complementary approaches.
Complimentary is strongly linked with:
- hotels
- flights
- restaurants
- customer service
- tickets
- gifts
- reviews
- praise
- marketing
Oxford lists “complimentary tickets,” “complimentary breakfast,” and “complimentary remarks” as standard uses.
What about country differences?
The key point is that the spelling does not change by country. US, UK, Canadian, Australian, and other major English varieties use complementary and complimentary with the same basic distinction.
What can change is search context. For example, searches connected with hotels and travel are likely to favor the “free” meaning of complimentary, while searches about color, teamwork, business, or science often use complementary.
For current country-by-country interest, Google Trends is the best live source because its relative-interest data changes over time.
The safest SEO strategy is therefore to target the combined phrase “complementary or complimentary” and answer both meanings clearly.
FAQs About Complementary or Complimentary
Is it complementary or complimentary?
Both are correct. Complementary means completing or working well with something. Complimentary means praising something or giving something free.
Is it “complimentary breakfast” or “complementary breakfast”?
It is complimentary breakfast when the breakfast is free.
Is it “complementary colors” or “complimentary colors”?
It is complementary colors.
Does complimentary mean free?
Yes. Complimentary can mean given free as a courtesy.
For example:
The hotel provides complimentary Wi-Fi.
Oxford lists “given free” as a standard meaning of complimentary.
Does complementary mean similar?
Not exactly. Complementary things can be different but work well together.
For example:
The two employees have complementary skills.
They do not need to have the same skills. Their different skills can complete each other.
Is “complimentary” a British spelling?
No. Complimentary is not simply a British spelling. Both British and American English use complimentary.
What is the easiest way to remember the difference?
Think:
Complementary → complete
Complimentary → compliment
If something completes or improves another thing, use complementary. If someone gives praise or something is free, use complimentary.
Conclusion
The difference between complementary or complimentary is simple once you connect each word with its meaning.
Use complementary when two things complete, support, or improve each other. Think of complete as your memory clue.
You can have complementary skills, complementary colors, complementary products, or complementary ideas.
Use complimentary when something expresses praise or is provided free. Think of compliment. You can receive complimentary feedback, make a complimentary remark, or enjoy a complimentary breakfast.
Most importantly, this is not a British-versus-American spelling issue. Both major forms of English use the same spellings. The real issue is choosing the word that fits your sentence.
For professional writing, always check the meaning before choosing the spelling. If you mean “works well together,” choose complementary. If you mean “praise” or “free,” choose complimentary.
Once you remember those two simple rules, this commonly confused pair becomes much easier to use correctly.
