There has been no greater invention for the progression of surfing than the leash. Since leashes hit the surf scene way back in the early 70s, surfing has surged in popularity, both professionally and as a pastime.
Allowing every level of surfer to push their limits without fear of losing their surfboard (most of the time) – the surf leash deserves all the praise that’s coming its way.

In this article, we are going to champion the mighty leash in all its surfboard-saving glory. We will do this, by highlighting its history, its various working parts, and most importantly, how to properly secure one to your surfboard.
Surfing is a super rewarding sport to master. Getting in touch with nature and pushing yourself while learning to glide across moving water is a life-changing experience.
But, as important as the surfboard under your feet is for learning, you can forget about your wave-shredding dreams without a decent leash. So, get ready to learn the leash today and master the waves tomorrow.
What Is A Leash And Why Is It Used?
Before we jump into the attaching aspect of your fresh-out-the-packet leash, it is a good idea to first learn what they are and why they are used. Maybe you’ve seen a piece of cord trailing behind a surfer as they’re riding a wave?
Or, maybe you’ve seen a surfer attaching something to their ankle down at the water’s edge before paddling out? Either way, this is their leash.
In the modern-day, leashes are made of lightweight, high-density urethane that is super durable while maintaining a little stretchiness.
The stretch of a leash is important as it reduces the amount of stress on a surfer’s leg when a wave is pulling them one way and their surfboard the other.
The sole purpose of a leash is to keep your surfboard attached to your body.
This is important because without a leash you run the risk of losing your board after hitting a wave that didn’t go quite to plan. If this occurs, your board may be lost at sea, damaged on the rocks, or come in contact with a fellow surfer.
The most likely scenario, however, is that it will be taken all the way to the beach, by the waves, leaving you out the back without your precious floatation device (your surfboard).
History Of The Surfboard Leash
The O’Neill family sure is a family of innovators. Not only did the iconic, eye-patch-adorning Jack O’Neill invent the wetsuit in 1952, but his son Pat O’Neill only went and invented the leash in 1971 too.
That’s not to say Pat’s first prototypes weren’t primitive pieces of equipment. But, as they say, Rome wasn’t built in a day, and neither was the leash.
So controversial was the leash in the early days that Pat was famously disqualified from the 1971 Malibu International Surfing Competition for attaching his prototype to his surfboard and paddling out.
This controversy stemmed from the idea that a leash was considered cheating, and looked down upon by the old guard of surfing. Although this archaic mindset quickly changed once the surf world caught wind of its exponential potential.
Made of surgical cord, the first leashes were prone to snapping in powerful surf. They were also far too stretchy. We know we said that stretch is a good thing, but too much stretch was, most definitely, a thing.
The first leashes would stretch out so far that they then had the precarious potential to hurtle back towards a surfer and injure them. In fact, this is how Jack O’Neill lost his eye in a tragic accident.
Thankfully, these days, surfing injuries as a result of leashes are rare at best, and their worth certainly outways the risk.
What Are the Different Parts Of A Surfboard Leash?
Learning the different parts of a leash comes with the territory of attaching one correctly to your surfboard. Once you know the why behind each part, you will be ripe and ready to attach your leash and hit the waves.
Ankle Strap
Ankle straps have the rather important job of keeping leashes attached to ankles. They do this through a heavy-duty strip of velcro.
Ankle straps also feature a thin layer of foam padding to offer ankle support. Without this padding, the tension of a stretched-out leash in a wipeout could result in an ankle injury.
Always make sure your ankle strap is attached correctly before paddling out and into the surf, because ill-fitting velcro is a common cause of people to lose their surfboards.
Don’t wait until this velcro has grown tired and, as a result, is starting to lose its grip. Replacing your leash before the velcro becomes tired is another clever way of preventing a wayward surfboard in the surf.
Cord
As previously hinted at, the cord is the long and strong part of a leash. Made of high-density urethane, leash cords are designed to handle high amounts of stress without snapping.
Leash cords will naturally stretch over time, especially if used in powerful waves. If you notice that the cord has been stretched out beyond its original length by more than six inches then it’s time to invest in a new leash.
An overstretched leash will be more dangerous to yourself and other surfers, as well as having a higher chance of snapping without warning.
Swivels
Think of the swivel as the joint of the leash. A joint that allows it to rotate in a 360-degree rotating range of movement. These days, most premium leashes will have two steel swivels attached, with synthetic nylon, to either end of the cord.
Double swivels allow a surfer to move freely in the water without the risk of their leash getting caught up in their feet.
Of course, this isn’t foolproof 100% of the time, but it greatly reduces the risk of leash and feet entangling.
Rail Saver
As we’ve pointed out, when the inevitable happens and you fall off your surfboard, your leash is going to be pulled extra tight. This tension is often focused on the rail of your surfboard’s tail as the leash presses hard against it, which, in turn, can cause damage to the surfboard.
The rail saver’s main reason for being, therefore, is to protect the surfboard at all costs. Made of heavy-duty nylon, these flat pieces of fabric can be pressed and rubbed against the surfboard tail without putting a depression in its fiberglass.
If the cord was to run all the way to the leash plug then it would result in many damaged surfboard tails.
String

The last piece to the puzzle is the leash string. It used to be that leash strings were sold as a separate product. However, in the modern-day, premium leash brands have gone above and beyond by fitting a leash string straight onto the rail saver.
This is great for two reasons. One, these fitted leash strings don’t require a knot that has the potential to come undone. And secondly, it’s one less thing for you to worry about, and buy.
If your leash doesn’t have a string already attached to it, then they are still sold separately at most reputable surf shops. Just make sure that you pull its knot super tight before going for a surf as a loose knot is another easy way to lose your board in the surf.
How To Choose The Correct Leash
As you may have already guessed – not every leash is made equal. Some are short, some are long, some are thick, and you better believe it that some are thin.
The why behind this comes down to the size of your surfboard and what kind of waves you expect to be surfing.
Leash Length
As a general rule of thumb, you want to make sure your leash is as long as your surfboard. It can be a little longer, but it should never be shorter.
This is the case because a leash that is too short has a greater chance of it bouncing back and hitting you underwater in the throws of a wipeout.
An example of this would be a 6ft shortboard requiring a 6ft leash. If your shortboard is 6’6ft, then a 7ft leash is best. This same rule can be applied for all surfboard lengths up to the very long at 9ft and beyond.
Leash Thickness
Measured in millimeters, and typically ranging from 5 – 8mm, leash thickness is another important aspect of its overall effectiveness. You may have overheard a leash be described as a “comp leash” before.
Comp leashes are the thinnest type of leash available at 5mm. Their reduced thickness means they are lightweight and create less drag in the water – perfect for high-performance surfing in competitions.
Suiting the majority of surfers is what the industry considers a “regular leash”. At 6mm thick, regular leashes are designed to handle waves in the 2 – 6ft range. Which, again, for the majority of surfers, is what they will be surfing most of the time.
However, there is an outlier to this rule as the increased weight of a longboard will require you to acquire a thicker leash at 7mm. The same can be said for surfers looking to surf waves at 6ft+ and above.
For these sizable conditions, a leash of 7 – 8mm is recommended as big waves subsequently mean more power.
How To Attach A Leash To Your Surfboard
You now know about surfboard leashes, inside, and out. So the only thing left to learn is how to attach one to your surfboard. Maybe you’ve never surfed before.
Maybe you’ve taken a few lessons where a leash was pre-attached to the surfboard. Maybe you’re at the exciting stage of buying your very first surfboard.
Whichever it may be, learning to attach a surfboard leash is an integral part of becoming an independent and proficient surfer, so let’s “duck dive” in.
Step 1
Attaching a leash to your surfboard is simple once you know what you’re doing. On the top side of your surfboard (the deck), down by the tail, you will notice a hole with a thin piece of metal fixed, side to side, across the top of it.
This purposefully-fitted hole is known as the leash plug. To attach a leash to your surfboard, all you have to do is push the looped-end of your leash string down one side, under the metal, and up the other side of the plug.
To help the string along, premium leashes come with a thin, inbuilt piece of plastic that helps you to feed the string through the tight leash plug hole.
If your leash doesn’t come with this plastic little helper, then any thin and hard object will do the trick. A stick, fork, knife, fin key, it doesn’t matter what it is, all that matters is that you work gently and don’t damage your surfboard in the process.
Step 2
Once the string has been fed under, and up the other side of the plug’s metal strip, it’s time to feed the velcro of the rail saver through the leash string.
This is a simple case of finding the end of the velcro and feeding it through both ends of the leash string. Once you have done this you will then need to fold the other piece of rail-saver velcro over the initial piece and make sure a tight seal is found.
The end result should be a leash string that is folded, in half, below the metal, and the velcro securely fitted through both ends of the string.
Then your leash will be securely fixed to your surfboard, and the only step left is to secure your ankle strap and paddle out with the satisfaction of knowing your surfboard won’t be going anywhere in a hurry.
Conclusion
Giving surfers the desirable ability to keep hold of their surfboards through thick and thin waters – the importance of the leash knows no bounds. Now that you’re in touch with your leash, what it is, where it came from, and how it came to be, the hard part is behind you, and now the fun part can start.
Surfing makes a good case for the best sport on earth. Allowing people to live in the moment by reacting to, and riding a wall of moving water – surfing is a sport that requires a high sense of awareness, skill, and patience.
With your trusty leash doing its thing, there will be no stopping you from riding a wave, falling, whipping your board around, and paddling back out for just one more.