Headshaking is one of the most distressing behaviours a rider can encounter. It ranges from occasional mild head tosses that feel like a training quirk to violent, repetitive shaking that makes a horse genuinely difficult — sometimes dangerous — to ride.

It is also one of the most misunderstood.

Many horses who shake their heads are labelled as difficult, sensitive, or simply "that kind of horse." In reality, a significant proportion of headshaking cases have a clear, addressable cause — and incorrectly fitted bits and bridles are among the most common culprits that are consistently overlooked.

This article covers what headshaking actually is, how equipment contributes to it, how to distinguish equipment-related causes from others, and what to do when equipment is the problem.

What is headshaking?

Headshaking is a repetitive movement — vertical (up and down), horizontal (side to side), or a combination — where the horse jerks, tosses, or shakes their head. It can be voluntary (a learned evasion) or involuntary (a genuine neurological or physical response to discomfort).

While headshaking can have medical causes — including trigeminal neuralgia, ear mites, dental problems, allergies, and light sensitivity — incorrectly fitting equipment is a significant and frequently unaddressed contributor. Ruling out equipment fit should always be an early step in any headshaking investigation, before pursuing more extensive and expensive veterinary work-ups.

How different types of headshaking relate to equipment

Vertical headshaking — up and down

The horse throws their head sharply upward and downward, often in a repetitive pattern that worsens when contact is taken up or collection is asked for.

This is most commonly associated with:

Poll and headpiece pressure — the poll is one of the most sensitive areas of the horse's body. It is where the first cervical vertebra (the atlas) meets the skull, a region rich in nerve endings with minimal soft tissue padding. A headpiece that sits directly on the atlas, a browband that is too short and pulls the headpiece forward into the ears, or a narrow headpiece that concentrates force in a small area can all create enough discomfort to trigger persistent vertical headshaking.

Bit-related mouth discomfort — a bit positioned too high in the mouth creating constant pressure and wrinkling at the corners, a single-jointed bit creating a nutcracker action that compresses the tongue and presses into the palate, or a bit that is too thick for the horse's mouth conformation can all trigger upward head movement as the horse tries to create space or relieve the pressure.

The upward head toss is the horse trying to relieve pressure — either at the poll or in the mouth. It is not defiance. It is communication.

Horizontal headshaking — side to side

The horse shakes their head from side to side, sometimes violently, as though trying to dislodge something from their face.

This is most frequently related to:

Noseband and facial nerve pressure — the facial nerve runs along the side of the horse's face, passing close to where nosebands typically sit. Pressure on this nerve does not just cause discomfort — it creates genuine neurological irritation comparable to the sensation humans experience when a limb "falls asleep" from nerve compression. The horse's response is almost involuntary: shake the head to relieve the sensation.

A noseband that is too tight, positioned too high (pressing on the prominent cheekbones), twisted, or simply the wrong design for that horse's facial conformation can all trigger this response.

Asymmetric bridle fit — cheekpieces adjusted to different lengths, a browband sitting at an angle, or a bit that is too wide and slides from side to side can create one-sided or alternating pressure that the horse tries to shake off with a lateral movement.

Combination and rotational headshaking

Some horses display complex patterns — circular movements, figure-of-eight motions, or alternating between vertical and horizontal. This often indicates multiple simultaneous sources of discomfort, or a horse that has developed a habitual shaking pattern in response to discomfort that has since become somewhat self-perpetuating even when the original cause is partially addressed.

Specific equipment causes — and how to recognise each one

Headpiece and poll pressure

What is happening: When rein contact is taken up, pressure transmits through the bit and cheekpieces to the headpiece, compressing the poll. The headshaking is the horse's attempt to relieve that compression — and the behaviour worsens during collected work where poll flexion increases the load on the headpiece.

Signs this is the cause:

• Headshaking worsens when contact is taken up or increased
• The horse is more settled in a looser, longer outline
• Sensitivity or heat behind the ears or over the poll after work
• Resistance to bridling — particularly when the headpiece goes over the ears
• Visible pressure marks or white hairs where the headpiece sits

Browband length

What is happening: A browband that is too short pulls the headpiece forward into the base of the ears with every movement of the horse's head. The headshaking temporarily relieves this pressure, which reinforces the behaviour — creating a cycle that can be difficult to break even after the bridle is corrected.

Signs this is the cause:

• The browband sits flat against the forehead with no gap between the browband and the head
• The headpiece sits visibly forward, on or near the ears rather than behind them
• The ears are pulled forward or appear uncomfortable
• Headshaking occurs consistently throughout work regardless of contact level

Noseband pressure and positioning

What is happening: As described above, noseband pressure on the facial nerve creates neurological irritation that the horse is trying to relieve through lateral headshaking. Unlike discomfort from the poll or mouth, which tends to produce more targeted responses, nerve irritation produces an almost irresistible urge to shake — which is why this type of headshaking can be particularly persistent and difficult to manage without identifying the cause.

Signs this is the cause:

• Headshaking is predominantly side to side
• The behaviour begins or worsens shortly after the noseband is fastened
• Loosening or temporarily removing the noseband produces improvement
• Visible indentations, marks, or sensitivity along the sides of the nose after work
• The horse rubs their face on objects when given the opportunity

Bit fit and positioning

What is happening: A bit that pinches, creates excessive tongue or bar pressure, contacts the palate, or sits incorrectly in the mouth is a direct source of discomfort that the horse will attempt to escape through head movement. Unlike poll or noseband-related headshaking, bit-related shaking tends to be closely tied to the moment contact is applied.

Common bit problems that trigger headshaking:

• Too narrow — pinching the lips at the corners
• Too wide — sliding through the mouth and creating instability
• Too thick — creating palate contact or tongue compression in horses with less mouth space
• Single-jointed with significant nutcracker action — compressing the tongue and pressing into the palate
• Positioned too high — creating constant wrinkling and pressure at the mouth corners
• Positioned too low — sitting on the teeth and creating instability

Signs this is the cause:

• Headshaking begins specifically when contact is first taken up
• The behaviour increases during transitions or when rein aids are applied
• Mouth opening, tongue evasions, or jaw crossing accompany the headshaking
• The horse shows immediate relief when the bit is removed after work
• Working in a bitless setup produces a noticeable reduction in the behaviour

For more on bit fit and the range of problems that arise from incorrect sizing, see our guide on why a correctly fitted bit matters.

Distinguishing equipment-related headshaking from other causes

This distinction matters because the investigation pathway is very different.

Equipment is likely the cause if:

• Headshaking begins when the horse is tacked up or immediately when ridden
• The behaviour worsens with increased contact or during specific movements
• The horse works freely without headshaking when worked in a halter or bitless bridle
• There are physical signs — marks, heat, sensitivity — where equipment sits
• Adjusting or changing equipment produces immediate improvement
• The pattern is predictable and consistent based on equipment use

Other causes are more likely if:

• Headshaking occurs when the horse is not wearing any equipment
• The behaviour is seasonal — suggesting pollen-related trigeminal neuralgia or light sensitivity
• The horse shakes their head in the field or stable when entirely unrugged and unequipped
• Veterinary examination reveals ear problems, dental issues, or neurological conditions
• The behaviour began suddenly without any equipment changes and persists despite equipment modifications

If you are uncertain which category applies, a systematic approach is the most reliable path: professional veterinary examination to rule out medical causes, followed by professional equipment assessment. These two things working together give the clearest possible picture.

What to do when equipment is the cause

For poll and headpiece issues

• Switch to an anatomical headpiece with wide, padded poll relief and generous ear cut-outs
• Check and correct browband length — it should sit with a finger's width of clearance between the band and the forehead
• Consider gel-padded or memory foam-padded headpieces for horses with significant poll sensitivity
• Ensure the headpiece is not being pulled forward by a short browband

For noseband issues

• Check positioning — the noseband should sit approximately two finger-widths below the projecting cheekbone
• Check tension — two fingers underneath is the minimum standard; more freedom is often better
• Try an anatomical noseband with nerve relief cut-outs specifically designed to avoid facial nerve pathways
• Consider whether the horse actually needs a noseband in its current form, or whether a different type would suit their facial structure better
• For some horses, removing the noseband entirely during an assessment period reveals how significant a contributor it has been

For bit issues

• Professional bit fitting to assess mouth conformation — palate height, tongue size, jaw width, and bar sensitivity all influence what bit will and will not work
• Try different widths systematically — correct width is typically measured so that the bit protrudes approximately 2–3mm either side of the lips
• Consider double-jointed or curved mouthpieces that reduce nutcracker action
• Explore different materials — sweet iron, copper alloy, and titanium all have different properties and some horses respond well to specific materials
• Adjust bit height so there are one to two gentle wrinkles at the mouth corners — no more, no less
• In cases of significant bit discomfort, trialling a bitless setup can help establish whether the bit is the primary cause before undertaking extensive bit-swapping

Prevention — and a note on listening

The best approach to headshaking is the same as the best approach to any equipment-related problem: regular professional assessment and a genuine commitment to listening to what the horse is telling you.

Annual bridle and bit fitting checks, combined with attentiveness to changes in behaviour, allow problems to be caught early — before habitual patterns develop and before physical damage accumulates.

Headshaking is not a personality trait. It is not stubbornness or sensitivity or "just how they are." It is a horse communicating, as clearly as they can, that something is not right. The ethical — and practical — response is to investigate, not to suppress.

If your horse shakes their head, do not accept it as a quirk. Start with the equipment they are wearing every time they work, because that is the most immediate and controllable variable — and one of the most common causes.

Key takeaways

✔ Headshaking is a communication, not a character flaw — something is causing it

✔ Equipment fit — particularly the headpiece, browband, noseband, and bit — is one of the most common and consistently overlooked causes

✔ Different headshaking patterns point to different likely causes — vertical to poll or mouth, horizontal to facial nerves or asymmetric fit

✔ Equipment-related headshaking is predictable and consistent based on equipment use; medical causes tend to present differently

✔ A systematic investigation — veterinary examination combined with professional equipment assessment — gives the clearest picture

✔ Many horses improve immediately or significantly when equipment fit is addressed

Is your horse a headshaker?

If your horse shakes their head under saddle, a professional bridle and bit fitting assessment is one of the most efficient first steps you can take — non-invasive, relatively quick, and often immediately revealing.

At The Fitted Horse, we assess bridle and bit fit as a complete system, looking at every component that could be contributing to discomfort. We cover Northamptonshire, Leicestershire, Warwickshire, Buckinghamshire, Oxfordshire and surrounding counties.

Book a bridle and bit fitting consultation →

Further reading: Signs your bridle may not fit correctly | The hidden costs of a poorly fitting bridle | Why a correctly fitted bit matters | Contact evasion in ridden horses