Choosing the right pontoon boat size first requires you to know how pontoon boats are measured. These boats are measured in terms of pontoon length rather than something like deck length, meaning the overall length is measured from the front of the tube at the bow of the boat to the rear at the stern. Therefore, if you have a 15 foot pontoon boat it is only the tubes themselves that are 15 feet from end to end. Your deck space will be slightly less at 14 or even 13 feet in total.  Inflatable pontoons tend to be on the small to medium size.

In terms of width, there is much less variation than there is with length, and most pontoons tend to be between 7 to 10 feet in width with 8 feet being the standard pontoon boat width, for the most part. Choosing the right pontoon boat size will definitely depend on what you plan on doing with your boat, so let’s take a look at some options.

Small Pontoon Boat Length

Length: Up to 18 feet

Capacity: Up to 5 – 8 passengers. Always check your specific boat’s weight/passenger limit to be sure

Ideal for: Cruising, fishing, relaxing, low intensity water sports

Cost: Most affordable

There’s no definitive standard by which anyone classifies small, medium and large pontoon boats but let’s say that any boats under 18 feet will qualify as a small pontoon boat. Most people would consider a small pontoon design for one to five people to be about 15 feet in length. That tends to be the short end of the scale for most recreational pontoons.

Companies like Pond King also market small pontoon boat sizes called mini pontoons that are designed to handle one or two passengers maximum. These vessels have a weight capacity of just 650 lbs or so and they may measure as small as 8 feet long by 4 feet wide on the deck with sets of four small pontoons that are five feet long, two on each side, that offer a maximum length of just over 10 feet when a small space between the tubes is included. These mini pontoons have seats for two, a trolling motor and literally nothing else. Essentially they’re floating fishing platforms which makes them very simple. They are obviously well suited for simple, no frills fishing but they are not cruising vessels by any means and with a trolling motor you would obviously never use this for water sports.

Most small pontoons can work as fishing vessels or recreational vessels for small families. With room for five you can use these for cruising, scuba diving, picnics on the water, etc. It’s not impossible to use a small pontoon like this for water sports but you would likely be experiencing some fairly tame sporting. Because the motors on smaller boats aren’t designed to be that powerful usually, you may find that trying to engage in something like tubing in a small pontoon difficult. Not impossible, but maybe not as intense as you like.

If you have younger kids, a small pontoon would probably still be fun for them and may give you more peace of mind as well since it’s less likely to be as fast and therefore not as dangerous as some more powerful boats.

Medium Pontoon Boats

Length: 18 to 24 feet

Passengers: 8 to 10 people

Ideal for: Fishing, cruising, small gatherings, water sports

Cost: Generally affordable relative to other boats but, when choosing highly specialized and luxury models, can get pretty expensive

Medium boats range between 18 feet and 24 feet. The width will probably be 8 feet to 10 feet at the most. You can consider these your average pontoon boat and boats in this range can be customized for as wide a range of activities as you can imagine. Boats that range from about 17 to 19 feet can accommodate about 8 people fairly comfortably.

Because a medium size pontoon boat is the most popular, manufacturers seem to put the most effort into giving you the best options with these sized boats. For that reason you can find medium pontoons that are specifically designed as fishing boats which contain lots of great features like live wells, extra storage, rod holders, chairs and more.

If you’re more interested in fun and recreation, you can get a lot of features like slides, swim platforms, even diving boards on some models. They also may feature extra comfortable seating, space on an upper deck for lounging in the sun and so on.

I would recommend medium pontoons as being the best pontoon boat for water sports as well in terms of bang for your book as it relates to fuel efficiency, horsepower and overall fun that you can have. Pontoons, historically, have never been speed demons and a lot of people dismiss them out of hand in terms of their towing capacity. But modern pontoons have some pretty powerful engines and you can get motors that draw 60 horsepower or more, making them more than capable of engaging in water sports. They will still never be as fast and furious as something like a jet boat, but for family water sport fun, a medium pontoon boat could really get the job done for you.

Large Pontoon Boats

Length: 24 feet and above

Capacity: 10+ passengers

Ideal for: Fishing, cruising, parties

Cost: Most expensive

The largest pontoon boats can clock in around 24 feet and get up to 30 feet in length, though that’s extremely large and very rare to see on the water ever. Once pontoons get over 25 feet they’re pretty bulky and rare to find,and also pricier as you can imagine. Some of these larger boats can be made extra wide as well, getting up to 12 feet wide or more. The problem with boats this large, of course, is that they’re harder to manage and costlier. Docking a larger boat, and a wider boat, can be a delicate and frustrating task. For some boaters, docking a pontoon boat can already be harder than doing the same task with a traditional vessel. So a large, wide pontoon boat compounds that issue significantly. I would not recommend something like this for a new boater.

Large pontoon boats are ideal as party boats compared to their smaller cousins. You can get 12 or more people on these boats and that’s the big selling point. If you’re not much of a partier and don’t expect to have a lot of friends out on the water for gatherings, these larger boats can still meet your needs if you have a big family. Because they accommodate many people, if you do summers with your extended family, or you just have a big family in general, then these larger pontoons will offer more room for everyone to be able to relax and have fun on the boat.

Naturally, with all the extra space you should be able to have a good time fishing with large groups from a boat of this size as well.

I would argue that the one thing a boat of this size is not suited for is water sports. Since pontoons are generally not super well suited for water sports anyway, a larger pontoon would just be less efficient. The motors on a boat this size could handle it, of course, and you can use a boat this size for things like tubing or water skiing. But if that’s your main point of interest, if you don’t need a boat this big to do it, I would stick with a medium or even small pontoon to get it done. It will be easier to manage and more economical in the long run.

Issues with New Pontoon Boat Measurements

I already touched on one issue with pontoon boat sizes and that’s the fact that they may be measured along the tubes or along the deck. So if someone says they have a 15 foot pontoon, you may need to double check if that’s the deck or the tubes. The longest overall measurement is what some manufacturers go by when they list dimensions in their boat specs which means whichever of the two is longest will be what they refer to – deck or tubes. However, some will only measure by deck even if the tubes stick out longer, so you may need clarification if you’re not sure. Pontoon boat dimensions can get confusing with new pontoon boats or even a used pontoon boat if someone is trying to oversell what they have.

Another confusing issue is that, traditionally, the model name of a boat can let you know the size. For instance, and this is just a made up example, but if you were looking at a Sunchaser 1765XLT, you could expect that the length would be about 18 feet. The first numbers in most model names, like that 176, would often mean 17.6 feet or about 18 feet in length. However, that’s no longer always true with a lot of newer models and you might find the boat actually 2 feet longer than that.

Sometimes manufacturers measure their boats not just from end to end of the tubes, but they will artificially inflate measurements from furthest point to further point. What that means is the total length might be from the tip of the pontoon at the front to the very furthest point on the outboard motor or a swim platform at the rear. Things that aren’t technically part of the boat at all are sometimes folded into the measurement which can be a little confusing.

Because some manufacturers or dealers can include extras, this can make choosing the right pontoon size more of an issue than you’d like. That’s why it’s good to clarify whenever possible what length overall is, but also tube length and deck length so you have a much clearer picture of the size of the boat, including the usable deck size which is likely what you’ll be most concerned with.

The Bottom Line

Pontoon boats are often split up into small, medium and large sizes. You can further divide small pontoons down into small and mini pontoons, where mini pontoons are under 15 feet and often down around 10 feet. Small pontoons may be considered anywhere in that 15 to 18 foot range, with some wiggle room at the smaller end where manufacturers may still label things mini. Medium pontoons tend to be over 18 feet and up to around 24 feet while anything longer than that might qualify as a large pontoon boat.

Choosing the right pontoon involves knowing what you want to do with the pontoon boat and what the pontoon boat costs. If you just want a boat for fishing with just one or two people, a small pontoon may be best. If you want to have fun and relax with the family while also potentially enjoying fishing and water sports, medium pontoons offer the greatest versatility and range of options. But if you have a big family or like to throw parties than a large pontoon will offer the most deck space to meet your needs.