What does a fin do on a paddleboard? | Poole Harbour Watersports

To paddleboard all you need is your board, the paddle and let’s not forget the fin. It can be easy to understand what the other two components do, but the purpose of the fin and how many you need is not always as clearly understood.

Most paddleboards, inflatable or hard, will have just the one single fin at the back. This fin helps you track through the water in a straight line, as well as providing some stability to stop you going side to side. Without this main fin in the centre, you will find that it is hard to paddle straight and the board will keep turning quickly left to right as you paddle (will make it hard to balance too!).

Paddleboard fin - Poole Harbour Watersports


Why does my paddleboard have more than one fin?

Sometimes paddleboards have one larger centre fin and two smaller fins as well, known as side biters. These are generally found on smaller, wider boards or those designed for surf. The purpose of these side biter fins is that they add a little more stability, particularly if you are surfing with your paddleboard and you want more stability on the rails when turning. Some beginner boards have these for the stable purpose, however they can cause added drag and slow you down, as such we wouldn’t focus too much on choosing a board for the 3 fins (one is enough!).


What fin is best for my paddleboard and the water conditions?

A standard SUP fin will be around 8-9” long and go in the centre of the back of the board and these are perfect if you are on flat water or the sea. Depending on where you are paddleboarding, you can also get different style and shape fins for the water.

What is a river fin?

Many of us like to paddleboard along the rivers and as such they can be very shallow and contain reeds. As such, you can get yourself a river fin designed to improve performance on the river, shallow to not hit the bottom of the river bed, and a more elongated shape to cut through reeds and improve tracking.

River paddleboard fin - Poole Harbour Watersports

What is a touring fin?

For those going out for longer on their paddleboard, they may be more inclined for a different shape fin that maximises glide, minimizes drag yet still provides good tracking. As such, they are not short fins but they have a more raked trailing edge (the shape of the fin is at an angle).

Touring paddleboard fin - Poole Harbour Watersports

What is a surf fin?

For surfing, you want a more reactive yet stable feel on your paddleboard. As such, many tend to have more than one fin and they are all a lot smaller. Many will have a thruster set up (1 large + 2 small side fins) or quad (4 small side fins); these smaller side fins allow the rider to step back on the ack of the board to lift the nose and turn, yet the fins along the back of the board provide stability and less drag.


Thruster paddleboard fin - Poole Harbour Watersports  Quad fin paddleboard - Poole Harbour Watersports


Check out our range of paddleboard fins to find the best one for you!


Another great blog about fins can be found here - 'Choosing a Paddleboard Fin'.

We hope you have found this helpful, if you have any other questions about paddleboards, please don’t hesitate to call 01202 700503, email info@pooleharbour.co.uk or even pop into our shop at Sandbanks.

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