* Atlantic Ocean
* Pacific Ocean
* Indian Ocean
* Arctic Ocean
* Southern Ocean
They also inhabit some seas within these oceans, such as:
* Mediterranean Sea
* Red Sea
* Black Sea
* Caribbean Sea
It's important to note that some species of dolphins are more common in certain areas than others. For example, bottlenose dolphins are found in all of the oceans listed above, while the Amazon river dolphin only lives in the Amazon River in South America.