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What Size Motor for a 20 Foot Pontoon Boat? Here is the Answer!

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what size motor for a 20 foot pontoon boats

Pontoons are becoming more and more popular due to their versatile nature. You can use them for fishing, leisure activities, and water sports. Skiers or kneeboarders can easily be hooked and pulled alongside a pontoon boat. In addition, it is flexible and easy to customize to the owner’s needs.

Owning a 20-foot pontoon boat can level up your fishing experience. However, how can you know what is the right-sized engine for your vessel? In general, experts recommend 115 horsepower engines for 20 to 25-foot pontoons. This varies a little depending on factors like boat use and maximum weight capacity.

In this article, we will break down the factors and help you know the answer to “What size motor for a 20 foot pontoon boat?

Table of Contents

What Is a 20-Foot Pontoon Boat?


Understanding what pontoons are, especially their functions and performance, will help you choose the accurate pontoon boat motors.

A pontoon has a flat and boxy deck. The deck shape allows this boat type to be spacious for leisure activities and entertainment purposes. However, it lacks the ability to move, point, and direct quickly on the water. This is why people only float pontoons on sheltered waters like rivers or lakes.

The motor plays a huge part in keeping the boat buoyant. In the past, a typical pontoon can speed at around 10 mph in good weather conditions. But now, depending on the size, pontoons can be equipped with a 115 to 200 hp engine and can move at speeds from 20 to 40 mph, or even more. For more specific pontoon boat motor recommendations, watch this video on Pontoon Boat Engine Size.

Even though designers have come up with many ways to upgrade pontoons in terms of speed, their performance is not the same as deck boats. It is because of the flat deck and hull shape.

Size Motor for a 20′ Pontoon Boat

In general, boats from 20 to 25 feet in length should have an engine of 115 horsepower. With this pontoon boat motor size, the top speed your 20-foot pontoon will reach is around 23 mph. You can always amp it up or lower it down a bit to your needs. Consider the following factors for the optimum engine.

Manufacturer Limits


Information about manufacturer limits can be found on the boat’s capacity plate or in the owner’s manual. It indicates the maximum weight a vessel can carry safely in good weather conditions. If you intend to go boating under bad weather, we recommend carrying half the allowed weight.

The average 20 ft pontoon boat capacity is around 3,000 pounds. It is a combination of the boat weight, people on board, engines, and appliances. Besides that, the capacity plate will tell the highest number of people the vessel can hold. A 20-foot pontoon can seat over ten people easily.

Please ensure safety by never exceeding the recommended weight. If loaded over the capacity, your vessel can go out of control, or even worse, swamp. Moreover, exceeding the capacity is a violation of the law in many states.

While checking the manufacturer limits, you will find the maximum horsepower recommended for your vessel. If you want your pontoon to perform at its top speed, choose an engine with its horsepower equal to this maximum number. You can’t exceed this number though. Please be aware that it is illegal to overpower a boat.

Number of People

Obviously, the more people the boat will carry, the larger its engine should be. Consider the number of people on board when you choose an engine. If only a few people are going to be on the vessel, a high horsepower motor might be a waste of money. Plus, the oversized engine can cause the pontoon to lean to the stern, which makes it difficult to control and direct.

Regardless of the number of people, you are thinking of, remember that the boat cannot carry more than what is stated in its capacity plate.

Pontoon Use

Last but not least, think carefully about what your pontoon is for. Will it have to carry out water sports activities? Or is it just for a family cruise in the afternoon? As said, most pontoons are for use on sheltered water but don’t underestimate the weight it might have to carry. Water sports like wakeboarding or water skiing demand a larger motor for the pontoon boat.

If you have a 16-foot aluminum boat, the motor size will have differences. Check this article to learn more now!


Choosing the right-sized engine for a 20-foot pontoon boat is essential to guarantee the best boating experience.

We really appreciate having you here. If you have further information about what size motor for a 20 foot pontoon boat, please share it in the comment section with our fellow boat owners. We are excited to learn from you. See you then!

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