Choosing the Right Marine Toilet for your Boat

Choosing the right toilet for your boat may not be an exciting shopping experience, but it's an important one.  The conveniences you add to your boat can determine the overall enjoyment you and your family have on the water.  For decades, boats have been outfitted with toilets that are cheaply made, difficult to operate, and not very comfortable.  Making the upgrade to a modern solution can make the difference for a fun weekend on the water.  When you invest in comfort and convenience, we can say with certainty that your family will thank you!

Modern marine toilets come in a variety of shapes, sizes and style.  There are also many variations of water sources, controls, and flush controls available. Knowing the right ones to choose can be a daunting task.  Here are five important factors to consider when selecting the right marine toilet for your vessel:

Types of toilets

Type of Operation

There are three typical types of toilets: portable, manual and electric. You should use portable toilets on smaller boats or where a fixed toilet and holding tank is not feasible.  Portable toilets are the most inexpensive type of toilet available. They offer an immediate labor-free solution for day boats that don't have a toilet. But, the waste tank capacity on portable toilets is minimal.  They don't offer a lot of comfort, they are messy to empty and clean, and they can emit foul odors where other solutions do not.

Manual toilets are typically lighter and less expensive than electric toilets.  They are designed for fixed/permanent installations and are plumbed to a remotely-mounted waste holding tank, thru-hull discharge, or waste treatment system.  Most manual toilets utilize raw water as the rinse water source (with a few exceptions) and do not require electricity.  Manual toilets eliminate the messy cleaning duties of portables, and they don't require a power source like electric toilets.

While they are the most expensive type of marine toilet, electric toilets are also more comfortable. Like manual toilets, electric toilets discharge to a remotely mounted waste holding tank, thru-hull, and/or waste treatment system. They can add more weight to the boat, require an electrical power source, and they can sometimes be noisy.  One of the most significant and most obvious differences between manual and electric toilets is the ease of flushing. Upgrading to an electric marine toilet will most closely match the operation of your household toilet at home and will undoubtedly improve the quality of life for you and your guests while out on the water.


A critical factor to consider when selecting a toilet is space. Knowing the specific height, depth and width available will be a determining factor in your toilet selection. A portable toilet is your only realistic choice if you don't have room for a fixed installation.  When comparing fixed toilet models, remember that the smaller bowl sizes are often referred to as Marine or Compact bowls. Larger-sized bowls are often called Regular, Household, or Comfort bowls.  A larger bowl refers to the diameter or toilet seat size, but height can also have a fairly significant impact on how you perceive the comfort level as well. Taking the time to review all of the provided dimensions will help you determine the differences that are most important to you.

Rinse Water Sources

Rinse Water Source

Rinse water evacuates effluent and rinses the toilet bowl clean. Toilets can utilize Raw Water (that is, sea or lake water) or Fresh Water (that is, onboard pressurized fresh water).  Some toilets, like the Raritan SeaFresh series, can utilize both rinse water sources depending on what is available. Manual toilets usually pump raw water to flush waste.  Utilizing raw water eliminates the need for an onboard pressurized fresh water tank and electricity.

Electric toilets offer a variety of options.  For instance, electric toilets that use raw water for flushing will typically include a remote or integrated intake pump to bring the water to the toilet.  One disadvantage of utilizing raw water is that it is more susceptible to bacteria/algae growth in the bowl which often results in a rotten egg smell, especially in salt water environments. Another disadvantage of raw water, specific to salt water applications, is calcium buildup/uric scale in sanitation lines. Calcium buildup happens when salt water comes into contact with urine. We highly recommend descaling your sanitation lines with products such as Raritan CH.

Electric toilets that utilize onboard pressurized fresh water will usually include a solenoid valve that allows water to enter the toilet.One possible disadvantage of fresh water the availability of potable water. If your boat has a smaller fresh water tank that is also used for other purposes (such as a shower or basin), you will need to monitor the consumption to ensure availability for flushing. The equipment that your boat is currently equipped with and what you have space for will determine the water source that is best for you.
Flush Controls

Flush Controls

There are a variety of flushing controls available on the market nowadays, especially for electric toilets.  Many electric toilets feature control panels which allow you to reduce the amount of water used, therefore extending the capacity of your holding tank. Some flush controls feature wireless wall-mounted control pads which allow you to spend less time running wires.Some toilets use a handle flush similar to a typical household style toilet.  Manual toilets typically feature some sort of pumping handle for flushing. Lever action handles are usually easier to use than the traditional t-grip handles.

Other  Considerations

With so many brands and models available on the market, there are many toilet features to consider beyond the ones listed above.  Some toilets promote their lack of noise.  Others feature a soft-close lid and seat (broken lids and seats are one of our most popular selling replacement items for toilets).  Toilets with larger joker valves typically avoid clogging as often as those with smaller check valves.  Some electric toilets have a macerator integrated inside the toilet body; others require you to purchase and install a macerator pump separately.


When you are considering a toilet purchase or upgrade, it's wise to take your time and compare all of the features of the toilets available to get an idea of what would work best for you. With such a variety of brands, styles, and features available, deciding on the right toilet for your boat can be overwhelming.  To ensure you are choosing the best toilet to best suit your needs, be sure to consult your local marine mechanic, or call our experts at Marine Parts Source at (866) 388-0290.