Why does my dog pull on the leash?

3 min read Updated on October 8, 2026

In shortYour dog pulls mainly because it works: every time he pulled and you followed, he got rewarded. Most dogs also naturally move faster than we do, everything down the street is calling him, and often no one has taught him that only a loose leash moves forward. Walking without pulling is not instinct: it is learned, with patience, rewards and plenty of sniffing. Sometimes he pulls to get away from something that scares him.

What it often means

Pulling works: every time the leash went tight and you followed, he got what he wanted. The habit builds itself.
He is faster than you: most dogs’ natural pace is quicker than ours, and the leash holds him back the whole time.
Everything calls him: smells, dogs, people, squirrels. Excitement often peaks in the first few minutes of a walk.
No one taught him: loose-leash walking does not come naturally, it is a skill many dogs have never really been taught.
Sometimes fear: he pulls toward home or away from a noise, tail low and body hunched. That is a different problem.

Signals to read at the same time

The direction: toward smells and dogs means eagerness; toward home or away from a noise means fear.
The body: head forward, tail high, panting and deaf to you; or low, ears back, with worried glances.
The timing: only at the start, near the park, or the whole walk.
His breathing: coughing, gagging or wheezing when the collar tightens are signals not to ignore.
What he does at the sight of a dog: pulls to go play, or barks and lunges, which calls for different work.

What you can do

Stop as soon as the leash goes tight, and move on when it slackens: he learns that pulling pauses the walk.
Reward him often for walking by your leg, with a treat delivered right at the seam of your pants.
Make sniffing the reward: when the leash is loose, say “go sniff” and let him explore with his nose for a good while.
Switch to a well-fitted Y-shaped harness that leaves the shoulders free, and a longer leash, around 6 to 10 feet.
Practice first indoors and on quiet streets, a few minutes at a time, before taking on the park and its temptations.

When to see a vet

See a vet if your dog coughs, gags or wheezes when he pulls, especially a small or flat-faced dog: his windpipe or airways may be taking the strain. Also see a vet if he suddenly lags behind, refuses to walk or limps: joint pain, a paw pad injury or unusual fatigue often hide behind that change.

Frequently asked questions

Doesn’t a harness make dogs pull more?

Not really. A harness does not create pulling, it mostly makes it less risky for the neck. A dog who pulled on a collar will pull on a harness until he is taught otherwise. Pick a Y-shaped harness that leaves the shoulders free, and train alongside it.

Will a choke or prong collar fix it?

These collars work through discomfort or pain. They can injure the neck, cause coughing, and link other dogs or passersby to that pain, which can make a dog reactive. Loose-leash walking is learned better, and safely, with a harness and rewards.

Should I let him sniff or keep him at heel?

Both have their place. A 2019 study showed that after a few weeks of scent work, dogs became more “optimistic” in a cognitive bias test than after obedience exercises. Alternate: a stretch of loose-leash walking, then “go sniff” as the reward.

How long does it take for him to stop pulling?

It depends on his age, how long pulling has worked for him, and how consistent you are. With the same rules on every walk, for everyone in the house, you often see progress within a few weeks. Setbacks near the park or another dog are normal: go back to calmer places for a while.

Sources

The studies this page relies on, with a link to the original publication.

Duranton & Horowitz (2019). Let me sniff! Nosework induces positive judgment bias in pet dogs. Applied Animal Behaviour Science.After a few weeks of scent work, dogs became more “optimistic” in a cognitive bias test than after obedience exercises.

Mimo reads behavior. It does not replace a vet.