A Guide to Surfboard Fins: The Different Types and How They Work in the Waves

Whether you are an absolute beginner or an experienced surfer, the fins you choose for your surfboard will contribute greatly to your development, performance, and fun in the water. Surfboard fins are designed to provide control and stability in the waves and enhance the ability to surf with speed and precision. Just like surfboards themselves, surf fins come in a huge variety of styles and options. Read on to familiarize yourself with the main characteristics and the impact they have when surfing.

Glassed-In and Removable Surf Fins

Surfboards come with one of two specific fin types. Glassed-in fins are permanently attached to a board by way of lamination. They’re common on longboards, single-fin boards, and retro fish surfboards and produce smooth rides. Despite being an industry standard for a long, some surfers today see them as lacking versatility. They can also be expensive to repair and replace.

Removable fins are surfboard fins that can be easily removed, thus allowing surfers to use different setups on the same board. They fit into the corresponding boxes of a surfboard and are screwed on and off with a fin key or screwdriver. It’s as simple as finding the correct box and tightening the fins until secure.

Box Systems and Compatibility 

If you choose a surfboard with removable fins, then it will come with a fin box, which is a slot or plug located close to the board’s tail that can be fitted with various fin designs. Longboard fin boxes are widely cross-compatible. Most other surfboards will have one of the following box systems.

Dual Tab FCS Fin Box

FCS (or Fin Control System) has been the most commonly used fin system since its invention in the 1990s. FCS fins have two tabs or plugs that are fixed to the board with screws.

Dual Tab FCS II Fin Box

The newest development from FCS is a keyless fin system that is secured to the board with only a plug and doesn’t require screws. This fin box is also compatible with older FCS fins. 

Single Tab (Futures) Fin Box

Futures is the other major player in fin boxes. These fins are attached to the board via a truss base and screws. Some seasoned surfers consider these fin boxes to be stronger, less expensive, and easier to repair than other fin types — usually, you’ll only have to replace a broken fin. 

Different Surfboard Fin Configurations 

Grab your board, look at the tail section of the bottom side, and count the fine boxes. The amount of boxes correlates to the fin configuration. The following are the more popular fin setups:

Single Fin

The single fin is a traditional setup and is most often seen on longboards. It's best suited for surfing in small-to-medium-sized waves and bigger but less powerful conditions. The long and large size of single fins provides control, stability, and predictability on the board.

Twin (or Dual) Fin

Four-time world surf champion Mark Richards pioneered the twin fin set up in the late-1970s and early-1980s. This configuration offers a skateboard-esque feel to surfing with drawn-out turns. A twin fin setup is ideal for shortboards and excellent in small to small-medium surf. It creates speed and increased maneuverability. 

Thruster Fin (or Tri Fin)

Glance around a surf beach today, and you’ll likely see more thruster fin setups than any other. It’s a three-fin configuration with the center fin designed to create stability and the outer two to increase tracking and speed. This system holds up well in almost all conditions and can be changed to make single and twin fin setups. 

Quad Fin

Quad fin is a four-fin setup that combines the benefits of the twin and thruster setups. It works great in smaller surf conditions by channeling the water out of the board’s tail to increase speed. The back fins allow for fast turns similar to the twin fin boards, although with more control and stability. 

2+1 Fin

This is a variation on the thruster three-fin setup that’s gaining popularity with funboards and paddle boards users. The main difference is that the middle fin box is longer, which lets you use a longboard fin for extra stability. The side fins are there to improve drive and speed. 

5 Fin

Despite what the name suggests, a 5 fin setup isn’t a surfboard that uses five fins. Instead, it has five fin boxes that give you as the rider the freedom to create a configuration based on the current surf conditions and your riding preference. 

Finless

While surfboard fins are important, especially when offering stability for beginners, some surfers ride finless like on the old-school wooden alaia boards from Hawaii. This is best for experienced riders that like to go fast and have the ability to pick good lines on clean waves. 

Different Surfboard Fins for Different Kinds of Boards

Soft Top Fins

Most soft top surfboards come with soft plastic fins that are either glassed-in or attached via a fin box. Our Soft Top Surfboard Fins are compatible with almost all surfboards on the market and can be attached with a coin or flathead screwdriver. The rounded edges offer extra safety both in and out of the water. 

Soft Top Performance Fins

Those with a desire to increase speed and enhance maneuverability can opt for soft top performance fins. The SBBC Soft Top High Performance Fins are designed with the intermediate and advanced surfer in mind and are a great addition to a soft top surfboard.  A 50/50 foil on the center fin creates control, and the flat foil side fins offer reliability, especially in powerful surf.

Fiberglass Performance Fins

One of the traditional materials for surf fins is fiberglass, as the combination of fiberglass cloth and resin creates a strong and stiff fin. They are great options for traditional single fin and twin fin surfboards, where sturdiness is key. When waves are powerful, fiberglass fins are a go-to for their stability.  

Longboard Fins

Longboard riders typically use either a single fin or 2+1 configuration. The fin — the center one in the case of the 2+1 setup — should, as a general rule, be calculated as one inch of fin for every foot of board length. South Bay Board Co’s 9” Surf and Sup Single FCS Slot Fin is a superb choice for all surfing abilities riding longboards and standup paddle boards. 

Get the Surf Fins that Suit You Best

Like everything in surfing, choosing your fins depends on your personal riding style and the waves you ride. It might take time to find your favorite setup but be sure to have fun experimenting along the way.

See you in the water!