How Does a Boat Toilet Work? (Marine Toilet Requirements)

how does a boat toilet work

Whether or not you are an avid sea traveler is beside the point. If you have a curious mind, you should have, at one point in your life, asked yourself, “How does a boat toilet work?”

Fret not! It was only very recently that we discovered how boat toilets work and that there is actually more than one type of marine toilet, each of which offers different ways of disposal. It is now time to share our intriguing findings with you.

If you would like to know what kinds of boat toilets are installed in yachts, ferries, cargo ships, and military vessels, then continue reading this quick article!

The Different Types of Boat Toilets and How They Work

Interestingly enough, there is a wide range of marine toilets in the market today, from affordable and portable options to built-in premium devices. Listed below are three of the main boat toilets (identified technically as marine sanitation devices) that can be seen in both commercial and non-commercial vessels.

Portable Toilet/Cassette Toilet

A portable toilet or cassette toilet is the water equivalent of a porta-potty or mobile toilet. This type of toilet makes use of cartridges or cassettes that hold the waste that is excreted into the toilet bowl.

It differs from traditional toilets in terms of size (portable toilets/cassette toilets are smaller) and the way the waste is flushed down (either through a bellows-type flush system or a piston pump flush system).

This is a great option for smaller boats such as pontoons or deck boats where space is really a challenge. It is also good for those looking for budget options in the market or can simply serve as a backup or placeholder until other types of marine toilets are installed.

Another reason why portable toilets or cassette toilets are so great is because they can be moved from one position to another and can even be used in areas outside of the boat (say, for example, during camping trips or in RVs).

The issue, however, with this type of marine toilet is the fact that the cassettes or cartridges can only hold a limited amount of waste, so we would suggest bringing in extras to be sure that there is enough room for everyone’s excrement.

Manual Pump-out Toilet

A manual pump-out toilet is a direct step-up from a portable or cassette-type toilet. This toilet functions and looks similar to traditional land-based toilets and has a greater capacity to hold in more waste matter.

The great thing about this type of marine toilet is that it is the standard choice for most boat owners as it is the best mix of affordability, practicality, and durability.

The waste disposal method for this type of toilet (and the electric version) entails visits to the marina’s disposal area or even going out into the sea, far away from the seashore (depending on your state’s rules and regulations on waste disposal), which is definitely better than having to lug around cassettes or cartridges to land-based waste disposal areas.

The disadvantage, on the other hand, is the fact that installation is required, and once installed, moving it to another area of the boat would require another complete installation procedure.

Electric Pump-out Toilet

An electric pump-out toilet essentially functions the same way as a manual pump-out toilet with the key difference being, clearly, the electric capability of this type of marine toilet.

Electric pump-out toilets are the best because they are the closest to the modern-day toilets we get to use in most facilities and establishments, including our homes. These toilets do not require extensive learning and excrement can easily be flushed down at the press of a button.

There are a few disadvantages, however. The first of which is the price point of this type of toilet. With premium features and electric power comes a hefty price tag, so make sure you are financially ready for this kind of investment. Second, similar to this marine toilet’s manual counterpart, the installation would have to be done in a permanent area of the boat, so you better be sure where you plan to install this toilet as it will be extremely challenging (and costly) to position it elsewhere.

The Requirements for Marine Toilets

marine toilet

The Clean Water Act is the primary legal basis for what should and should not be done when it comes to the installation and operation/use of marine toilets. There are several stipulations indicated, but the key points are to ensure that the marine toilet is fixed and pumpable.

In addition to the requirements mentioned, here are a few more factors and considerations to think of before deciding on which type of toilet boat to get for your vessel.


As is the case with every boat-related investment, setting aside a decent budget for marine toilets should be considered deeply.

Portable toilets or cassette toilets can be availed of at around the $200 - $400 range, while manual and electric pump-out toilets typically begin at around $500 and can go up to as high as $2,000, depending on the overall size and installation requirements.

If you are rather limited when it comes to budget, then go for portable or cassette toilets. However, if you have the money (and time) to spare, look into getting an integrated manual or electric pump-out toilet.


Boats that are purchased for private or non-commercial use are pretty small which is why it is important to consider space and room when investing in a marine boat.

There is no cut and dried method of determining the size of your marine toilet in reference to the overall length or dimensions of the boat. What we would recommend instead is to take identify a space, room, or area in your boat that is private enough that can be used as a lavatory or bathroom.


Again, just like how space has to be considered given the generally small sizes of personal or non-commercial vessels, so must weight.

Typically, marine toilets add anywhere from 20 pounds to 50 pounds of weight to the boat. This has to be considered when the overall boat capacity is limited and must be computed together with the passengers as well as the gear and equipment that will be brought aboard the boat.

Make sure to be well within your vessel’s weight capacity before setting out to sea.


If you are looking to get the more expensive premium electric pump-out boat toilet, then you would also have to consider wattage and power requirements.

Most modern-day electric marine toilets are efficient when it comes to power use but you would still have to keep an eye on how much power it actually needs and what the voltage of the outlet should be.

The voltage would typically be either 12 volts or 24 volts, so if you have a boat and are looking to install an electric pump-out toilet after the fact, make sure you have outlets that are capable of accommodating the boat toilet’s requirements.

Chemical Cleaners and Deodorizers

This goes without saying but we feel the need to mention it anyway: it is very important to have the typical toilet sanitizers and deodorizers aboard ship just to be sure that everything is clean and hygienic.

You don't to be stuck on a boat that has a messy toilet area as a result of clogging or overflowing, right?

To make sure you are prepared for any bad boat toilet possibility, have a bunch of chemical cleaners and deodorizers on hand. On a side note, toilet bowl cleaners can also be used to clean the pontoon.

Frequently Asked Questions

Let us answer some of the most commonly asked questions regarding boat toilets (or marine toilets) below.

Can you poop in a boat toilet?

Yes, it is completely acceptable to poop in a boat toilet. However, we would ultimately recommend either pooping ahead of time before the boat trip or holding off your poop session until you get to shore (assuming you can hold your poop in for a little bit longer). A lot of marine toilets, portable or otherwise, are designed to be capable of sucking in larger amounts of waste, but due to space restrictions and storage capacity limitations on a boat, frequent pooping may not be the most ideal situation.

Are marine toilets easy to install?

Some marine toilets are easy to install, while others are not. The installation requirements of a marine toilet primarily depend on the type of marine toilet to be installed. If we are talking about a portable or cassette toilet, then the installation would be very quick and easy. If we are talking about pump-out toilets that are built-in, then it would require expert installation mechanics to ensure that the waste disposal system is properly integrated.


Boat toilets are so interesting. The design and engineering that went into each type of marine toilet just go to show how creative and innovative people are just to make sure that people or passengers have a great time during sea travel. So, if anyone asks you, “How does a boat toilet work?” you would definitely be more than capable of answering the question.

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