In short: first identify the type of harness (over-the-head or step-in), present it calmly, close the buckles under the belly, then adjust each strap. The harness is on properly when it does not twist, does not slide forward and does not rub under the front legs.
Putting on a harness looks easy, until the day your dog wriggles, a strap ends up the wrong way round or the harness slips after five minutes. Here is a step-by-step method that works for most walking harnesses, followed by the adjustments to check before you go out.
1. Identify the type of harness
Before putting it on, lay the harness flat and identify its parts: the neck strap, the chest strap or straps, the chest plate (the part that covers the chest), the back and the attachment rings. There are two main families:
- The over-the-head harness: the neck loop goes over the head, then one or two straps close under the belly, behind the front legs. This is the most common shape for walking.
- The step-in harness: your dog puts their front legs into two loops, then you lift the harness up and close it on the back. It suits dogs who don’t like having something passed over their head.
Your first reflex if in doubt: follow the manufacturer’s diagram. A harness put on the wrong way round works badly and can rub.
2. Get your dog ready
- Choose a calm moment, not the moment your dog is jumping for joy at the door.
- Open all the buckles and loosen the straps slightly before you start: it is easier to tighten than to force.
- Keep a few treats to hand. Rewarding each step makes handling pleasant, especially at the beginning.
3. Putting on an over-the-head harness, step by step
- Stand beside or behind your dog rather than facing them: they feel less trapped and you can see which way the straps go.
- Hold the neck loop in front of their nose, chest plate downwards and back ring upwards. You can hold a treat on the other side of the opening so they put their head through on their own.
- Slip the head through without pulling on the ears. The chest plate should rest on the chest, between the front legs.
- Bring the belly strap round behind the front legs, without catching it in an armpit.
- Close the buckles. You should hear a clear click. Pull gently on each buckle to check it holds.
- Centre the harness: the back ring should be in the middle of the back, the chest plate in the middle of the chest.
4. Putting on a step-in harness
- Lay the open harness on the floor, with the two leg loops clearly visible.
- Guide one front leg into each loop, starting with the one your dog lifts most easily.
- Lift the harness up the legs to the shoulders.
- Close the buckle or buckles on the back, then adjust.
5. Fitting the harness: the points to check
A harness that is closed is not necessarily well fitted. Take a minute to check:
| Check point | What you should see | If not |
|---|---|---|
| Strap fit | You can slide your fingers flat under each strap, with no room for more. Two fingers is a common guide. | Too tight: loosen. Too loose: your dog may back out of the harness. |
| Neck strap | It sits at the base of the neck, without pressing on the throat. | Adjust the neck strap, or check the size. |
| Belly strap | It runs behind the front legs, away from the armpits. | If it rubs under the legs, the harness may be too small or badly placed. |
| Shoulders | Your dog walks and trots normally, without shortening their stride. | A horizontal strap that sits too low can get in the way: try another adjustment or another shape. |
| Stability | The harness stays centred after a few steps. | See our article on a harness that twists to the side. |
Do one last test: gently pull the lead forward then backward. The harness should not ride up onto the throat or slip over the shoulders.
6. Where should you clip the lead?
- Back ring: for a dog who already walks calmly on the lead. The lead runs above them and rarely tangles.
- Front ring (on the chest): it turns your dog to the side when they pull, which helps you guide them. The lead can get under the legs: we explain how to avoid this in this article.
To go further on this question, read Do no-pull harnesses really work?
7. The most common mistakes
- Choosing the size by weight rather than measurements. Chest girth matters more. If you don’t have a tape measure, here is how to measure your dog without one.
- Tightening “to be sure”: a harness that is too tight restricts breathing and rubs.
- Adjusting once and for all: the coat, grooming, weight gain or weight loss all change the fit. On a long-haired dog, check as close to the skin as possible (our method).
- Leaving the harness on all day: take it off at home, especially if your dog is left alone. A strap can catch or rub.
8. My dog refuses the harness: what can I do?
Many dogs don’t like having something passed over their head. Don’t force it: you risk linking the harness with restraint. Start again in small steps, rewarding each one:
- your dog sniffs the harness lying on the floor;
- you bring the opening close to their head, then they put their nose through to take a treat;
- they put their whole head through, and you take the harness off straight away;
- you close one buckle for a few seconds, then both;
- they wear the harness for a few minutes at home, then outside.
If your dog licks their lips, turns their head away, yawns or moves away, go back to the previous step. These subtle signs show discomfort. A step-in harness can also be a good alternative.
Frequently asked questions
How do I know the harness is the right size?
Once adjusted, it should not rub under the front legs, press on the throat or be able to slip over the head when your dog backs up. If you are at the end of the adjustment range in either direction, the size probably isn’t right. Our article on a dog between two sizes covers the borderline cases.
How often should I check the fit?
Glance at it every time you go out, and check more carefully after grooming, a bath, a change in weight or with a growing puppy.
Can the harness be left on overnight?
It is better to take it off. The harness is for walks: worn all the time, it can irritate the skin and get caught.
Sources
- Dogs Trust, Introducing a harness (step-by-step habituation and signs of discomfort).
- Battersea, Train your dog to wear a collar, lead or harness.