Why Do Dogs Smile? Grin, Submissive Smile or Warning

By Tailwisp Editorial TeamUpdated October 17, 20263 min read

Dog faces can look strikingly like they are smiling. Some of those expressions are happy, some are appeasing, and some are warnings.

The relaxed open mouth

A relaxed dog may hold the mouth slightly open, with the tongue loose and the lips soft. The eyes are soft, the ears are in a natural position and the body is loose. This looks like a smile and often means comfort. It is common after play or walks.

The submissive or appeasing grin

Some dogs pull back their lips and show front teeth while wiggling, crouching or lowering their head. This is sometimes called a submissive grin. It tends to come with soft eyes, a relaxed body and a wagging tail. Dogs use it to greet people and other dogs peacefully. Because it shows teeth, newcomers may mistake it for aggression.

The learned human smile

Some dogs seem to pull their lips up in a human-like smile around their favorite person. It may be learned, since people respond with delight. It may also be inherited in certain lines. The research on this is limited.

Teeth-baring as a warning

Aggression looks different:

• Stiff, still body, often leaning forward
• Hard stare
• Wrinkled muzzle
• Closed mouth, then lip curl
• Growling. See why do dogs growl
• Raised hackles

Do not punish warning signals. They give you time to prevent a bite. See dog stress signals checklist.

Panting versus smiling

Dogs pant to cool off and sometimes when stressed. A dog with tight lips and rapid panting may not be smiling. Watch the eyes and body. See dog hot weather safety.

Breed differences

Breeds with flat faces, loose lips or wide mouths may look like they are always smiling or frowning. Compare with your own dog's normal.

Safety around grins

Teach children that a dog showing teeth needs space, even when wagging. Introduce new dogs slowly. Never lean over a dog's face.

Common mistakes

• Reading all teeth-showing as aggression.
• Assuming every smile is friendly.
• Forcing a dog to tolerate kisses.
• Ignoring stress signals around the smile.

Troubleshooting

• My dog grins at visitors and visitors panic: explain the grin and ask guests to stay calm and ignore.
• My dog's lips look tight: check for stress or pain and consider a vet check.
• My dog's smile ends with a snap: talk to a behavior professional. See when to see a dog behaviorist.

A simple plan

1. Note when your dog grins and what the rest of the body does.
2. Reward calm, polite greetings.
3. Keep greetings short and low-pressure for new people.
4. If you ever see tension with teeth, give space and call a professional.

What smiles look like across dogs

Every dog has a personal style. Some Labradors and golden retrievers show a wide, open-mouthed grin after exercise. Some shepherds rarely show anything but a closed mouth. Some small dogs wrinkle their noses and pull back their lips when excited. Photograph your own dog in different moods and compare. You will quickly learn which expressions are friendly for your dog and which are signs of strain.

Smiling and temperature

An open mouth can simply mean the dog is warm. If your dog looks like he is smiling in hot weather, with fast panting and a very wet tongue, he may need water, shade and a rest. Always check the temperature before assuming the expression is purely emotional. A smile that fades into heavy, noisy breathing needs attention right away.

The takeaway

A smile on a dog is not always a smile. Look at the eyes, the body and the context, and you will know what your dog is saying.