Why Do Dogs Lick Each Other? Here's What They're Actually Saying

Affection and Social Bonding

The most straightforward reason — and a real one. Dogs who like each other lick each other. It's a physical expression of comfort and connection, the same way humans might put an arm around a friend.

Ruby does this with dogs she's comfortable with. After an initial meeting that goes well, she'll settle in next to another dog and start grooming their ears or face. That's not just hygiene — that's her saying we're good, I like you, I'm relaxed around you.

Mutual licking between dogs who know each other well is one of the purest forms of canine social bonding. It's the same mechanism as the oxytocin loop we see between dogs and humans — physical contact that creates and reinforces connection.

Submission and Respect

In dog social dynamics, licking is one of the clearest submission signals that exists. A less dominant dog licking a more dominant dog is saying — in very plain language — I acknowledge you, I'm not a threat, we're good here.

It comes from wolf pack behavior where lower-ranking wolves would lick the faces of higher-ranking pack members as a form of deference and respect. Domestic dogs kept the behavior because it works. It communicates something important without requiring any kind of conflict.

When Ruby encounters a dog who is very confident or assertive, she will often do a quick face lick early in the interaction. Not from fear — from social intelligence. She's smoothing things over before they need smoothing.

The Mouth Lick — A Wolf Behavior

This is the one that looks strangest to humans and has the deepest roots.

Wolf puppies lick the mouths of adult pack members to stimulate food regurgitation — it's how they get fed when they can't hunt themselves. The adult wolf returns from a hunt, the puppy licks their mouth, the adult regurgitates partially digested food. That's the original function.

Domestic dogs no longer need this behavior for food. But the mouth lick persisted as a social greeting — a way of saying hello, I'm excited you're here, I acknowledge you. When a dog licks another dog's mouth or lips at a greeting, that's ancient wolf communication happening in your living room.

The dog at the park who went straight for Ruby's mouth wasn't being weird. She was being very, very dog.

Appeasement — The "Kiss To Dismiss"

This one is counterintuitive. Sometimes a dog licks another dog not out of affection — but because they want the other dog to back off.

It's called appeasement licking or a "kiss to dismiss." The dog doing the licking is saying — please don't escalate this, I'm not a threat, can we just move past this moment. It's a de-escalation strategy. A peace signal.

The tell is context. Appeasement licking often happens when a dog is feeling crowded, pressured, or slightly anxious about another dog's behavior. The lick isn't warmth — it's a social tool to prevent things from going sideways.

Ruby uses this occasionally with dogs who get in her personal space too aggressively. A quick lick on their face and then she steps away. Translation: we're fine, but I need some room.

Grooming

Dogs groom each other. It's practical, it's social, and it targets the spots a dog can't easily reach themselves — behind the ears, the back of the neck, the top of the head.

Mutual grooming between dogs who are comfortable with each other is a sign of a well-established bond. It's not random licking — it's deliberate and focused. Ruby will spend several minutes on another dog's ears if they let her. It's one of her favorite things.

Dogs who groom each other are also reinforcing their bond through touch. The grooming is functional and social simultaneously. And dogs who have good outlets for energy and stimulation tend to do better socially too, which is part of why I like things like puzzle toys for keeping dogs balanced outside of social settings.

Information Gathering

Dogs get information through licking. Taste and scent together tell them things that a sniff alone doesn't.

Licking another dog's face, ears, or body gives them information about that dog's health, emotional state, what they've been eating, where they've been, and potentially their reproductive status. It's a full data download in a few seconds.

When a dog meets another dog and goes straight into licking — they're not just being friendly. They're reading them. Getting information. The lick is both a social gesture and a sensory investigation happening simultaneously.

Anxiety Or Stress

Sometimes repetitive licking of another dog is a self-soothing behavior driven by anxiety. The licking itself is calming — it releases endorphins and gives the anxious dog something to focus on.

The tell here is the quality of the licking. Relaxed social licking looks different from anxious compulsive licking. The anxious version is more relentless, more focused, and continues even when the other dog is clearly over it.

If your dog is licking another dog obsessively and the other dog keeps moving away or showing signs of annoyance — that's worth paying attention to. It may say more about your dog's stress levels than their affection for the other dog. In those situations, I’ve looked into options from Nutramax’s supplement line for that kind of support.