Behavior or Behaviour – What’s the Difference?

There are many English words that are spelled and pronounced similarly. Some of these words are homophones: words that are pronounced the same but mean different things.

Still, others are spelling variants that result from differences in American and British spelling conventions.

The latter is the case for the words behavior and behaviour. They are actually alternate spellings of the same noun, being are used in different language communities. Choosing one or the other doesn’t need to be difficult, but many writers are not aware of the differences between these words and make avoidable mistakes.

You don’t have to be one of them.

What is the Difference Between Behavior and Behaviour?

In this article, I will compare behavior vs. behaviour. I will use each of these spelling in example sentences, so that you can see them in context.

Plus, I will show you a helpful memory tool that you can use to remember whether behavior or behaviour is appropriate for your own writing.

When to Use Behavior

Define behaviour and define behavior What does behavior mean? Behavior is a noun that refers to observable actions, usually those of a person or animal.

For example,

  • The wildlife photographer observed the behavior patterns of a rare species of otter and documented his discoveries.
  • The new teacher tolerates a large amount of disruptive behavior in her first grade classroom.
  • The predatory behavior of big cats makes for fascinating television.
  • I’ve always had a penchant for this type of behavior, but it didn’t begin to interfere with my life until I got sober two decades ago. –The New York Times

Behavior is the standard form of this word in American English.

When to Use Behaviour

behavior english spellingWhat does behaviour mean? Behaviour is the British spelling of the same word. It has all the same meanings as behavior, and British writers use it in all the same contexts that American writers use behavior.

For example, most British publications will use behaviour,

  • Haldane offers no explanation for this burst of irrational behaviour. Nor can he: to him, irrationality simply means behaviour that is inconsistent with the forecasts derived from the BoE’s model. –The Guardian

Here is a graph that shows the usage of behaviour vs. behavior in British English,

behavior versus behaviour

Here is a comparable chart, focusing solely on American English,

Definition of behaviour definition and definition of behavior definition

These charts aren’t scientific, since they only look at English books written since 1800. As you can see, however, they clearly point to American standardization around behavior and British standardization around behaviour.

Trick to Remember the Difference

Behaviour and behavior are two versions of the same word.

  • Behavior is standard in American English.
  • Behaviour is standard in British English.

You will notice that behaviour has an extra U, just like United Kingdom, where behaviour is much more likely to be used. This is the memory tool that will help you choose between these words.

Behavior and behaviour also follow similar spelling difference between American and British English, such as color vs. colour, labor vs. labour, honor vs. honour, and others.


Is it behavior or behaviour? Behavior and behavior are two versions of the same noun, which means observable actions performed by a person, animal, or machine. Even though they mean the same thing, they are used in different language communities.

  • Behavior is standard in American English.
  • Behaviour is standard in British English.

Notice that behaviour has an extra U– just like the U in United Kingdom, where behaviour is likely to be used.

There are many differences between American and British English, and knowing your audience will help you write clearly and effectively to achieve your goals.

Remember, any time you have a question about confusing words, you can check this site for an explanation. And if you are ever stuck choosing behaviour or behavior, be sure to check back with this article.