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A composting toilet vs cassette toilet choice comes down to water and emptying. A composting toilet separates liquids and solids, uses no water and no chemicals, and empties without a dump station, while a cassette toilet flushes with fresh water into a removable tank that empties at a dump station. Pick the composting side for a cabin or van that stays put for weeks, and the cassette side for an RV that moves between campgrounds with dump stations.
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The quick answer: composting toilet vs cassette toilet
Choose a composting toilet if the cabin or van stays in one place and you want to empty without a dump station: the TRELINO separates liquids and solids into 1.2 gallon and 1.6 gallon containers, and the Nature’s Head holds enough for 2 people using it full time to empty every 4 to 6 weeks. Choose a cassette toilet if the RV moves between campgrounds: the Kohree listings hold 6.34 gallons of sewage and 5.3 gallons of fresh water for about 130 to 140 flushes, and the tank detaches for emptying at a dump station. The gear section below ranks all 4 listings by score.
How a composting toilet works
A composting toilet keeps liquids and solids apart so each can be emptied on its own. The TRELINO Evo S uses a separation and drying function to prevent odors, with a urine container of 1.2 gallons and a solid waste container of 1.6 gallons, and the listing says the toilet avoids chemicals and water, so it stays independent of dump stations. The Nature’s Head is a self-contained composting toilet with a close quarters spider handle design, and the listing claims no odor and no maintenance, with an empty that takes 5 minutes. The TRELINO measures 13 by 15.4 by 11.7 inches and supports up to 330 lbs, while the Nature’s Head stands 20 inches high, weighs 28.0 pounds and measures 20.98 by 19.02 by 20.98 inches. Both suit small spaces such as a van, a tent or a car, per the TRELINO listing.
How a cassette toilet works
A cassette toilet works like a small flush toilet with a removable tank. The Kohree listings flush with fresh water from a 5.3 gallon tank into a sewage tank of 6.34 gallons, for about 130 to 140 flushes before the tank needs emptying. The wheeled Kohree adds a level indicator that alerts when emptying is needed, a paper towel holder and a cleaner storage spot, plus wheels and a built-in handle for moving the unit. Both Kohree listings describe an upgraded cover lock and valve lock, an air release valve and high-density HDPE and PP materials to contain liquids and odors, and both support a weight capacity of 450 lbs. The wheeled listing gives dimensions of 14.1 by 18.9 by 17.3 inches in its bullets while the spec table lists 18.3 by 14.1 by 17.71 inches, so the two figures differ and the bullets win on size. See our how to clean an RV toilet guide for tank and seal care.
Capacity and emptying
Capacity decides how often you empty, and the two sides measure it differently. The composting listings state container sizes and use counts: the TRELINO holds 1.2 gallons of urine and 1.6 gallons of solids, with space for 9 to 11 Number One’s and 6 to 8 Number Two’s, while the Nature’s Head holds enough for 2 people using it full time to empty every 4 to 6 weeks. The cassette listings state flush counts: 5.3 gallons of fresh water gives about 130 to 140 flushes into a 6.34 gallon sewage tank. Emptying differs too: the composting containers lift out separately for cleaning, while the cassette tank detaches with a press of the tank button and rolls away on wheels on the wheeled Kohree listing.
| Toilet | Type | Capacity | Emptying |
|---|---|---|---|
| Nature’s Head | Composting | 2 people, 4 to 6 weeks | 5 minutes, per the listing |
| TRELINO Evo S | Composting | 1.2 gal and 1.6 gal | Separate containers |
| Kohree with wheels | Cassette | 6.34 gal sewage, 5.3 gal fresh | Detachable tank, dump station |
| Kohree | Cassette | 6.34 gal sewage, 5.3 gal fresh | Detachable tank, dump station |
The gear
The 4 listings rank by score below, with the Nature’s Head first on its 5-year warranty and full-time capacity, the TRELINO next on its separation design and 2-year warranty, and the two Kohree cassette toilets after them on flush capacity and odor containment, with no warranty term stated on either Kohree listing. The wheeled Kohree edges ahead of the other Kohree on its wheels and level indicator.
| Toilet | Type | Capacity | Warranty |
|---|---|---|---|
| Nature’s Head Composting Toilet | Composting | 2 people, 4 to 6 weeks | 5 Year Warranty |
| TRELINO Evo S Composting Toilet | Composting | 1.2 gal and 1.6 gal | 2 Year Manufacturer |
| Kohree Portable Toilet with Wheels | Cassette | 6.34 gal sewage | Not stated |
| Kohree Portable Toilet | Cassette | 6.34 gal sewage | Not stated |
Nature’s Head Composting Toilet: a self-contained composting toilet with a close quarters spider handle design, a 5-year warranty and a 28.0 pound weight. The listing claims no odor and no maintenance, with an empty in 5 minutes for 2 people using it full time over 4 to 6 weeks. It suits a cabin or van that stays put for weeks; skip it if the budget needs a smaller unit or a stated size beyond 20 inches high.
TRELINO Evo S Composting Toilet: a portable composting toilet with a 1.2 gallon urine container and a 1.6 gallon solid waste container, a 2-year manufacturer warranty and a 330 lb weight capacity. The separation and drying function prevents odors without chemicals or water, and the listing states a size of 13 by 15.4 by 11.7 inches. Note the spec table lists 33.0 by 39.0 by 29.6 inches, which cannot describe this toilet, so the title and bullets win on size. It suits a van, tent or car; skip it if a larger capacity or a longer warranty term is needed.
Kohree Portable Toilet with Wheels: a cassette toilet with wheels, a level indicator, a paper towel holder and a cleaner storage spot, with 6.34 gallons of sewage capacity and 5.3 gallons of fresh water for about 130 to 140 flushes. The cover lock, valve lock and air release valve contain liquids and odors, and the unit supports 450 lbs. It suits an RV that moves between campgrounds; skip it if a warranty term is needed, since none is stated.
Kohree Portable Toilet: a cassette toilet with the same 6.34 gallon sewage capacity, 5.3 gallon fresh water capacity and 130 to 140 flushes as the wheeled listing, with a paper holding place and detergent storage place, and a 450 lb weight capacity. It has no wheels and no level indicator stated, so it suits the same RV use at a lower feature count; skip it if wheels or a level indicator matter.
Which should you choose?
Choose a composting toilet if the cabin or van stays in one place, you want to empty without a dump station, and a 4 to 6 week emptying rhythm suits the household, as the Nature’s Head listing shows, or a small portable unit suits the van, as the TRELINO listing shows at 13 by 15.4 by 11.7 inches. Choose a cassette toilet if the RV moves between campgrounds with dump stations, you want a familiar flush with fresh water, and about 130 to 140 flushes per fill suits the trip, as the Kohree listings show. Either way, check the size on the listing before you order, since the page states sizes from 13 by 15.4 by 11.7 inches to 20 inches high. See our where to buy a portable toilet guide for buying options.
FAQ: power away from the grid
Do composting toilets smell?
The listings say no. The TRELINO listing says the separation and drying function prevents odors, and the Nature’s Head listing claims no odor at all. The Kohree cassette listings describe a cover lock, valve lock and air release valve to contain liquids and odors.
How often do you empty a composting toilet?
The Nature’s Head listing says 2 people using it full time empty every 4 to 6 weeks, with an empty that takes 5 minutes. The TRELINO listing gives space for 9 to 11 Number One’s and 6 to 8 Number Two’s before the containers need emptying.
How many flushes does a cassette toilet give?
The Kohree listings state about 130 to 140 flushes from 5.3 gallons of fresh water, with a sewage capacity of 6.34 gallons. The wheeled listing adds a level indicator that alerts when emptying is needed.
Do I need a dump station for a composting toilet?
No, per the TRELINO listing: by avoiding chemicals and water, the toilet stays independent of dump stations. A cassette toilet needs a dump station for its removable tank.
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