Newfoundland mix puppies, or "newfies", are a hybrid of a Newfoundland crossed with another dog breed. These are not purebred dogs. "Newfies" are often crossed with Labradors because they are similar breeds with similar coats.
Other popular "Newfie" mixes include the Golden Newfie, which is a Newfoundland crossed with a golden retriever, and Newfoundlands mixed with standard poodles. They are most frequently mixed with Labradors because the two breeds are similar in temperament, are both avid swimmers, and eat approximately the same amount. The two breeds also counterbalance each other in terms of temperament. For example, a Newfoundland is a calmer dog, while a Labrador is more excitable. While it is possible for a Newfie to be mixed with just about any large dog, Labrador hybrids tend to be the most popular.