Split Nails (Horizontal And Vertical) Causes And Fixes

If you’ve ever noticed what looks like a ridge or crack traveling horizontally or vertically across one or several of your nails, you could be dealing with something known as split nails.

While a single split nail can initially appear to be a superficial, cosmetic problem, if left untreated, split nails can cause more serious issues, from long-term brittleness to infection.

Split Nails (Horizontal And Vertical) Causes And Fixes

Luckily, there are some quick, temporary fixes to horizontal and vertical split nails, as well as more permanent treatments and preventative measures to maintain your nail health in the future.

In today’s article, we will be exploring the various causes of vertical and horizontal split nails and how you can approach remedying this problem.

We’ll also be answering all your most pressing questions about split nails in general.

What Is A Split Nail?

A split nail is either a fingernail or toenail that has essentially cracked either horizontally or vertically.

This usually occurs where there has been damage to the layers of keratin protein that make up human nails.

The damage can be external (for example, trauma, such as dropping something heavy on your nail) or internal (dietary or hormonal).

You might also hear a horizontal split nail referred to as Lamellar Dystrophy, Onychoschisis, or Onychoschizia since these conditions can cause nails to split.

If a nail splits vertically, meaning from the tip of the nail down towards the nail bed, this may be caused by a medical condition called Onychorrhexis.

It should be noted that vertical and horizontal split nails can occur simultaneously, in which case, the medical diagnosis would be something called Brittle Nail Syndrome.

This condition is so named because, when nails split both ways, their strength and resilience are significantly compromised, causing them to break easily.

While split nails are more common amongst women and elderly people, the conditions that cause split nails can occur in anyone of any age. Moreover, split nails can be caused by external factors.

Horizontal Split Nails vs. Vertical Split Nails

Determining whether your nails are splitting horizontally or vertically (if this is a recurring issue with no obvious external cause) can be instrumental in figuring out how best to treat the issue and assessing the severity of the situation.

As we mentioned above, horizontal and vertical split nails are typically caused by different conditions and have separate names within the medical field.

Horizontal split nails are referred to as Onychoschizia, while vertical split nails are often caused by and called Onychorrhexis.

But the differences don’t stop there. Vertical split nails are usually more difficult to remedy than horizontal split nails because they can actually cause damage to the nail bed, which may cause more serious complications.

Causes of Horizontal and Vertical Split Nails

While horizontal and vertical split nails are named differently in a medical context, nail splits in both directions can have similar causes. The main causes of vertical and horizontal split nails are as follows:

Nail Trauma

One of the most obvious causes of both vertical and horizontal split nails is direct trauma to the nail itself.

Nail trauma can occur in various forms, from catching and tearing the nail on something sharp to slamming your finger in a door.

Whatever the exact cause, exerting too much pressure or otherwise injuring your nail(s) can cause a horizontal or vertical split.

The good news is that if your split nail is a one-time occurrence caused by external trauma, you probably don’t need to worry about underlying health conditions or making changes to your lifestyle in the future.

Nail Biting

Nail Biting

Depending on how you look at it, nail-biting could come under the subheading of nail trauma.

However, nail-biting is such a widespread habit that is so difficult to break, and many people do not realize how habitual chewing can impact their nail health in the long term.

Biting or even picking at your nails puts stress on the layers of keratin, which may result in splitting.

Chemical Exposure

Many of us use chemicals every day in the form of household cleaning products. While products like bleach are really helpful when it comes to maintaining a clean home, they’re not so great for our skin or our nails.

Too much exposure to chemicals can cause nails to split either horizontally or vertically. This is why it’s recommended to wear gloves when handling harsh chemicals.

Cosmetic Use

A specific subcategory of chemical that often comes into contact with nails is cosmetics. Certain nail polishes or nail polish removers containing acetone can be responsible for horizontal and vertical nail splitting.

If you’ve noticed some horizontal or vertical ridges in your nails (which can lead to splitting) it might be tempting to try and cover them with cosmetics.

However, this won’t do your nails any favors moving forward.

While we’re on the subject of cosmetics, nail extensions, acrylic nails, and even press-on nails can cause nail stress, leading to eventual splitting.

Excessive Moisture

Everyone knows that thorough hand washing is important to keep germs at bay.

However, if your hands spend too much time submerged in water (through washing your hands, swimming, cleaning, etc.) your nails might sustain some damage.

Soaking your nails regularly makes them softer, which also causes them to become more susceptible to splitting.

Moreover, repetitive drying of hands after washing can lead to nails drying out, which is another cause of split nails.                                                                                                                                     


If you’re not getting the right nutrients in your diet, your body will lose some of its natural ability to grow and repair itself. This applies to all parts of your body, including your nails.

A diet that is lacking in protein may cause nail splitting because our nails are essentially made out of protein.

Nail splitting can also be the result of not consuming enough essential vitamins and minerals. Vitamin C, iron, and folic acid are all crucial for nail health.


Whether it’s a bacterial infection, a fungal infection, or even a yeast infection, any kind of infection of your nail or nail bed has the potential to cause splitting.

The reason infections are so detrimental to nail strength is that they alter the texture of the nail, meaning that the nail may become softer or drier.

Soft or dry nails are prone to splitting, hence the causation between nail bed infections and split nails.

Health Conditions

Apart from infections, there are various health conditions that can, as a side effect, cause split nails of both the horizontal and vertical variety.

Psoriasis, which is a skin condition that affects between 2 and 3 percent of the world’s population, is one of the leading medical causes of split nails.

In fact, research has indicated that around 78% of individuals with psoriasis will experience some decline in nail health.

Crumbling and thickening of the nails are not uncommon in psoriasis, and these symptoms can also result in split nails.

More serious medical conditions, such as kidney and liver disease, hypothyroidism, skin cancer, and diabetes may cause nails to split vertically or horizontally.

If you have noticed that your nails have begun to split alongside other symptoms, it is worth making an appointment with your doctor to rule out any underlying health conditions.

Fixing Split Nails

Fixing Split Nails

So, you’ve determined whether you’re dealing with a vertical or horizontal split nail, and maybe by this point, you’ve even identified the cause. But what now?

Well, as we always say, prevention is better than a cure, which is why we’ll be delving into different preventative measures to protect against split nails in a moment.

For now, though, rest assured that there is a relatively quick, temporary fix for split nails.

You will need:

  1. Teabag
  2. Nail polish remover
  3. Cotton ball
  4. Scissors
  5. Nail file
  6. Clear base coat nail polish
  7. Clear top coat nail polish

Step 1: Clean Your Nails

You’ll need a clean canvas to work on, so make sure to wash your hands and remove any existing nail polish before you try to fix your split nail.

If you’re wearing nail polish, remove it using some nail polish remover (not an acetone-based one, if possible, as these products can cause further damage) and a cotton ball.

Pro tip: just rest the cotton ball on your nail for a few moments and then gently wipe the color away.

You don’t want to do any further damage to your nail by applying excessive friction, and this method actually prevents staining, too!

Step 2: Make A Patch

If you were curious, here’s how the teabag comes into play.

Using your scissors, cut the teabag into a patch in the shape of your nail. You can simply discard the tea leaves as you won’t be using them – or reuse them for another purpose if you prefer.

Try to ensure that the patch fits within either side of your nail with no overlap as this will produce the neatest and most durable results.

Step 3: Apply A Base Coat

Once your patch is ready, you can go ahead and apply a thin, even layer of your chosen base coat to your split nail.

While the coat is still wet, apply your teabag patch over the top so that it sits smoothly over your nail. There should be no folds, creases, or bubbles. If there are, do your best to smooth these out.

Now, wait for the base coat to dry. Different polishes will have different drying times, but we would always recommend waiting for at least 5 minutes to ensure complete dryness.

Step 4: Apply A Top Coat

When you’re sure that the base coat is dry and that the patch is securely adhered to your nail, apply a layer of your chosen top coat.

Again, wait for it to dry (about 10 minutes) before moving on to any further steps.

Step 5: Finishing Touches

One final coat of nail polish and a quick filing down of any uneven edges should complete your DIY split nail fix!

If you want to apply colorful nail polish, you can now do so.