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Best composting toilet

Which composting toilet is best?

If you're looking to live off-grid or spend more time camping far away from facilities, the number one question is all about number two: what do you do with human waste? If you are looking to conserve resources and maybe even produce something useful for the garden, a composting toilet is the way to go.

For its odor control, ease of use and expanded capacity, the Nature's Head Self-Contained Composting Toilet is the best choice. 

What to know before you buy a composting toilet


Composting toilets are a great solution when you need a bathroom on a boat, in a van or in a cabin, but size matters. Because many commercial composting toilets store the waste, they can be larger than even the smallest plumbed toilets. Measure carefully to make sure the composting toilet you choose fits in the space you have. 


Capacity concerns how much waste the toilet can hold before needing to be emptied. Larger families need a high-capacity toilet, but singles and couples can get away with smaller holding tanks. 

The larger the composting toilet, the less frequently you will need to empty it. Keep that in mind if you want to cut down on basic maintenance tasks. 

Portable or built-in

The beauty of a composting toilet is that it can go anywhere you want it to. It's not tied to plumbing or water supply. However, even composting toilets can be built-in and more permanent. If you are adding a bathroom to an off-grid cabin, you might consider a built-in toilet that is fixed to the floor or the wall, but for travel or camping, a portable one is best. 

What to look for in a quality composting toilet

Separate liquid waste tank

The main concern most people have with composting toilets is odor. A primary cause of odor is liquid waste. To keep odor down, a separate liquid waste tank is a good idea. This can also be emptied before solid waste is emptied, diluted with water and poured directly onto nitrogen-loving plants.

Composting crank

As with outdoor garden composting, turning the material results in faster decomposition. Some composting toilets feature a composting crank that moves the waste around to hasten its breakdown. 

Leakproof and odorless

Especially for vans, boats and RVs, the last thing you want is a leaky composting toilet. While it's always advisable to empty your waste tank before moving the toilet, sometimes that's just not possible. Look for toilets with leakproof seals or single-body construction. This also helps trap any odors inside of the toilet until it can be emptied. 

How much you can expect to spend on a composting toilet

True composting toilets are more complex than simply collecting waste in a plastic bag and throwing it out. Expect to spend $150-$1,500 on a good system. 

Composting toilet FAQ

How does a composting toilet work?

A. Composting toilets follow the same principles as a garden compost pile. Gardeners add food scraps, leaf matter and plant material to a bin, rotating it and adding water. Natural bacteria (and worms in many cases) attack the pile and slowly break it down, creating a rich humus that adds nutrients back to the soil when used in the garden.

Composting toilets use solid and liquid waste, plus bulking materials like peat moss, sawdust or coconut coir, as the raw materials to create usable organic material. As with the garden compost, turning the material in the toilet helps aerobic bacteria quickly break down waste.

The process is simple.

  1. Add a bulking agent to the toilet (if needed; some toilets do not require this).
  2. Use the toilet as usual.
  3. Add more bulking agents if required.

From there, composting toilets differ. Some have a button that operates a heater and a fan to speed up the composting process, while others trigger a sealing feature after each use. Regardless, the waste will begin to break down and eventually become safe for disposal.

Can you use composted waste on plants?

A. As a general rule, human waste should not be used on any type of plant unless it is composted properly. This means that all of the material has broken down and is essentially sanitized by bacteria. After that, composted human waste is safe to use on plants that are not destined for human consumption.

If you are interested in using human waste for growing food, it's best to add composted waste to an outdoor compost pile and allow it to process for a year. At that point, it is exactly the same as other types of compost and can be used to fertilize plants. 

What’s the best composting toilet to buy?

Top composting toilet

Nature's Head Self-Contained Composting Toilet

What you need to know: This is a good option for more permanent, mounted installations.

What you’ll love: It is high capacity — two people using this full-time will only need to empty it once a month. There is no odor, but it comes with a fan. This is also covered by a five-year warranty.

What you should consider: It’s expensive for only occasional use.

Where to buy: Sold by Amazon

Top composting toilet for the money

Kohree Portable Toilet 

What you need to know: Choose this for camping, boating and other short outdoor trips.

What you’ll love: It holds nearly 6 gallons total, so use this up to 60 times without emptying. It has a carrying handle and is easy to set up. A water gun uses fresh water for cleaning after you use the toilet (like a portable bidet). 

What you should consider: Some users report leaking when moved, so be sure to empty and clean this before packing up.

Where to buy: Sold by Amazon

Worth checking out

Separett Villa

What you need to know: This is another option for more permanent, full-time use off-grid.

What you’ll love: Mount this on a wall for stable, regular use. It needs a 12-volt battery but can also run on an AC adapter to power a ventilation fan. It’s easy to install and comes with everything you need to set it up.

What you should consider: It’s a high-quality choice but comes with a hefty price tag.

Where to buy: Sold by Amazon


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Suzannah Kolbeck writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.

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