Our editors independently research, test, and recommend the best products; you can learn more about our review process here. We may receive commissions on purchases made from our chosen links.
Best Overall: Nature's Head Composting Toilet with Spider Handle
There’s no shortage of advocates for the Nature’s Head Composting Toilet with Spider Handle. This composting toilet is easy to install and simple to use. It has made a name for itself with its low maintenance needs and an odor-free operation.
While originally intended for marine applications, this composting toilet from Nature’s Head is frequently installed in RVs, cabins, outhouses, tiny houses, and more. This version equipped with a spider handle is frequently chosen for its space-saving design, though a more conventional crank handle model is available also. It boasts a considerable capacity for solids—60 to 80 uses, while also easily handling toilet paper. The liquids container will need to be emptied daily or every other day, according to users.
For some, the Nature’s Head Composting Toilet is their first introduction to composting waste management—and nearly everyone is impressed by how easy it is to utilize this commode. A number of people said they were apprehensive at first but have been pleased with all aspects of this composting toilet, including how effective it is at odor management. It’s wired for 12V power to keep the exhaust fan operational.
Some people experienced minor troubles with the exhaust fan or found it necessary to upgrade the unit to a more powerful fan. The only other frequent modification is to add finer mesh screen to the external vent to keep out tiny nuisance insects, such as no-see-ums.
Best for Odor: Sun-Mar Excel Self-Contained Composting Toilet
Odor management is a top concern when shopping for a composting toilet, and the Sun-Mar Excel Self-Contained Composting Toilet addresses this issue with unique features aimed at eliminating smells.
The Excel model from Sun-Mar sets itself apart from other composting toilets with a thermostatically controlled heater that aims to evaporate liquids quickly, thereby reducing odors. A rear fan also assists in evaporation and odor management by channeling a flow of air over the evaporating chamber before expelling it out a vent stack. It should also be noted that this composting toilet boasts NSF Standard 41 certification for its composting ability.
Users find the function of this composting toilet to be as promised, with many positively noting the lack of odors when using this model. However, a few people found the step to be precarious and suggest replacing it with a wider, more stable option.
Best High Capacity, Non-Electric: Sun-Mar CENTREX 3000 NE (Non-Electric)
A central composting system is the best solution if you’re in need of a high capacity composting toilet since it features a considerably larger composting system. The Centrex 3000 is a non-electric option that can be installed in off-grid applications where a power supply is lacking.
The unit comes fully assembled, and just requires a connection to a gravity flush toilet of your choice that uses one pint (or less) per flush. Unlike many models of composting toilets with self-contained composters, the Centrex 3000 is equipped to handle 5 adults for residential use or up to 8 adults for seasonal use. How frequently you need to empty the unit will depend on use, but the manufacturer states that central composting systems only require emptying every few months for full-time use and once or twice a year for seasonal use.
For individuals that don’t want the hassle of frequently emptying a self-contained composting toilet, a central composting toilet system is a worthwhile investment.
Best High Capacity, Electric: Sun-Mar Centrex 3000 Electric Composting Toilet System
If you have space for a central composting toilet system and a power supply, consider the Centrex 3000 for a high-capacity composting toilet. This model can handle the needs of up to 6 adults for residential use or 9 adults with seasonal use.
Unlike other models of high capacity central composting systems, the Centrex 3000 features an autoflow design that moves composted material along into a collection chamber. This eliminates the typical ‘drawer’ design that must be emptied on other composting toilet systems. Instead, the collection chamber makes it easy to dispose of finished compost.
People that have installed this high capacity composting system and paired it with a compatible dry toilet are typically very satisfied with the unit’s performance and report low to no odors.
Best Compact: Sun-Mar Spacesaver Electric Waterless Self-Contained Composting Toilet
If you’re short on space, consider a compact composting toilet. The Sun-Mar Spacesaver Composting Toilet requires less room for installation while still providing eco-friendly waste management.
The Sun-Mar Spacesaver model measures just 19.5 inches wide and 23 inches deep, requiring total depth clearance of 38 inches. Other models of composting toilets require up to 46 inches of clearance for installation. This compact composting toilet is an especially good option for boats, tiny houses with limited bathroom space, or small RVs. It costs considerably more than conventional composting toilets, but if space is at a premium, then it may be worth it to consider this space-saving model.
A smaller commode also means a smaller composting bin, so expect to empty this unit more often. For seasonal use, it’s rated for 3 adults, but if you plan to use it full-time in a residential capacity, it’s more suited for 1 adult. People that have installed this compact composting toilet mention that the seat is higher than expected, and it may be necessary to replace the somewhat small step that is included with the toilet.
Best Portable: Sun-Mar GTG Portable Electric Waterless Toilet
If you’re looking for a portable composting toilet that can turn just about any space into a private privy, check out the Sun-Mar GTG Portable Electric Toilet.
This composting toilet is a newcomer to the market, but Sun-Mar is one of the leading manufacturers of composting toilets. The GTG model simply plugs into a 110V outlet (adaptor for 240V outlets included) and features a divider for liquid and solid wastes. Optional mounting brackets are included if you want to make the GTG a more permanent fixture.
Since this composting toilet is designed to go anywhere, it forgoes the standard composting chamber on more permanent fixtures. Instead, a solids bin that must be lined with composting liners is used to collect waste and will need to be regularly emptied. This model is a step up from camping toilets, however, thanks to the exhaust fan and vent to keep odors under control.
Best Non-Electric: Sun-Mar Excel Non-Electric Touchless Flush Composting Toilet
If off-grid living is your thing, you’ll need a non-electric composting toilet. Sun-Mar offers its popular Excel model in a non-electronic version that enables you to cut ties with the power supply while enjoying the convenience of an easy-to-install composting toilet.
The Excel Non-Electric Composting Toilet includes a vent kit for keeping odors to a minimum along with a diverter for solid and liquid waste. This model is certified by NSF. The 11-inch bowl height came as a surprise to some users, and the included step needed to be replaced with a sturdier and wider option in some cases.
People have mixed opinions on living with this non-electric composting toilet. Some have experienced issues with leaking, while other users say that if the drain is installed properly this model will offer years of worry-free use.
Best Budget: Stansport Portable Toilet
For a budget composting toilet, consider using a portable camping toilet lined with disposable composting bags. The Stansport Portable Toilet is a sturdier and more comfortable option when compared to many DIY composting toilets using 5-gallon buckets.
If you don’t mind using biodegradable liner bags and making more frequent trips to empty the commode, then using the Stansport Portable Toilet as a budget composting toilet is a great alternative to spending $900 or more for a conventional composting toilet. The Stansport will support up to 350 pounds of weight, and while some people were skeptical at its relatively small size, most reviewers said they were impressed with its capacity.
For a composting toilet at a fraction of the cost, try the Stansport Portable Toilet for your next camping trip, boondocking RV trip, or during long weekends at your off-grid cabin. While its small size and dependence on biodegradable bags might not make it an ideal full-time composting toilet, it’s a great alternative for short-term use or occasional needs.