Complimentary vs. Complementary

Watching TV today while trying to catch up on the backlog of emails I have for the podcast, I saw the following commercial:

It’s a commercial (a site I am not familiar with), and seeing it made me think that I should write to explain the difference between the two words complimentary and complementary, as they are one of many pairs of words in English that are pronounced the same, but spelled and used differently.

Complimentary (with an “i”) has two main uses. It stems from “compliment”, which is when you praise someone or something. “John complimented my new kitchen.”¬†This sentence shows that John likes the new kitchen, and said something nice about it, called a compliment, and thus he was being complimentary. The other use of complimentary, the “i” version, is to mean something is free, usually in a restaurant or a hotel or such. For example, at many Mexican restaurants in America, you receive complimentary chips and salsa with any meal. At a hotel, you will probably find complimentary soap and shampoo in the bathroom.

The other complementary (with an “e”), is used differently. It is used to say that one person or thing goes with or works well with another person or thing. For example, “Your purse complements your blouse.” This means the purse and the blouse look nice together, they go together. Another example, “This wine really complements the veal.” This means that the wine tastes very good with the veal, they work well together. ¬†Another usage of the “e” version of complementary is a bit less common, but still important. “This aircraft has a complement of 7 crew members and 1 pilot.” The usage is similar, it means that the aircraft has 7 crew members and 1 pilot with it.

Back to the commercial I saw. Here is the dialog used:

Guest: “You even charged me for…the complimentary bottle of water!”

Hotel: “It’s complementary, with an ‘e.’ The water complements the room, it’s not free.”

Hopefully that will help distinguish the two words — unfortunately, you will see native speakers using the wrong one sometimes, but just keep in mind the meanings! If you have questions about specific examples, post them in the comments.