For most RVs, the Dometic 410 gives you a porcelain bowl at an 18-inch seat height; the Dometic 400 has a lighter all-plastic bowl for small trailers and vans. Both use a universal 2-bolt mount that Dometic says fits rough-ins of 7-5/8 inches and up.
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This guide covers gravity-flush RV toilets.
RV toilets compared
| Toilet | Bowl and build (maker) | Choose it when |
|---|---|---|
| Dometic 410 (9610008259) | Porcelain round bowl, plastic base, 18-in. seat height | You want a residential feel and easy-clean porcelain |
| Dometic 400 (9610008275) | All-plastic round bowl, tall | Weight matters, such as in a small trailer or van |
Most RV toilets are gravity-flush: pressing the foot pedal opens a valve at the bottom of the bowl and water rinses waste straight down into the black tank below. They are not the same as a household toilet, which uses a water-filled trap and a tank, so you need a toilet made for RVs.
Dometic 410: porcelain bowl
Choose the Dometic 410 for a residential-style RV toilet. Dometic lists (dometic.com) the Complete 410 with a porcelain round bowl on a durable plastic base, an 18-inch seat height, a soft-close lid with detent hold, a 360-degree rimless rinse, a compact 17.75-inch depth, a universal 2-bolt mount that fits 7-5/8-inch and larger rough-ins, tool-free ball seal replacement and a reinforced valve with a two-year warranty. Dometic says the 400 series is tested to twice the front load of a leading competitor and 150,000 flush cycles.
On October 15, 2026, the standard new offer from CWDS showed stock with part 9610008259 (white).
Check Dometic 410 porcelain RV toilet (9610008259) on Amazon →
Dometic 400: lightweight plastic bowl
Choose the Dometic 400 to save weight. Dometic lists (dometic.com) the Essential 400 as a tall gravity-flush toilet with an all-plastic round bowl, soft-close seat, compact rear profile, the same 7-5/8-inch rough-in and 2-bolt mount as the rest of the 400 series, and a reinforced valve with a two-year warranty.
Plastic bowls are lighter than porcelain, which matters in small trailers and vans where every pound counts. On October 15, 2026, the standard new offer from CWDS showed stock with part 9610008275.
Check Dometic 400 plastic RV toilet (9610008275) on Amazon →
Will it fit your RV?
RV toilets mount to a floor flange over the black tank with two bolts. Dometic says its 400 series fits rough-ins of 7-5/8 inches and up, measured from the wall behind the toilet to the center of the flange, and is designed as a universal replacement for Dometic and other brands. Measure yours before ordering.
Check the seat height and depth against your bathroom too. Dometic lists an 18-inch seat height for the 410 and a compact 17.75-inch depth for the series; it also sells a shorter 411 version of the porcelain model (Dometic 411 (dometic.com)) for tight spaces.
Also check the water inlet location and the supply line from your RV’s water system so the new toilet’s connection lines up.
Porcelain or plastic?
Porcelain bowls feel like a home toilet, resist scratches and stay looking clean. Plastic bowls are lighter, which helps in small rigs, but a plastic surface can show wear over time. Dometic offers both in the same series so the mounting and parts match.
Both picks here flush with a foot pedal, which keeps hands off the toilet. The owner’s manual explains how your model’s pedal adds water to the bowl and flushes, and it is worth reading before the first trip, since RV toilets work differently from the toilet at home.
Keeping the seal working
The ball seal at the bottom of the bowl holds a little water to block tank odors. If the bowl will not hold water, the seal may need cleaning or replacing; Dometic says the 400 series seal can be replaced without tools. Use the cleaners and lubricant the toilet maker recommends, since harsh chemicals can damage rubber seals.
Toilet paper sold for RV black tanks is designed to break down quickly, and using plenty of water with each flush helps solids reach the tank instead of building up under the toilet.
Winterizing
An RV toilet’s water valve can crack if water freezes in it. When you winterize, drain the fresh water system, follow your RV maker’s procedure for blowing out lines or adding RV antifreeze, and flush the toilet until antifreeze appears in the bowl. Never use automotive antifreeze in a potable water system. Our outdoor faucet winterizing guide covers related cold-weather steps at home.
Other RV toilet types
Gravity-flush toilets over a black tank are the most common in travel trailers and motorhomes, but not the only kind. Dometic also lists cassette toilets, which hold waste in a removable cassette emptied at a dump station, and portable toilets for vans and camping. Some larger coaches use macerating toilets that grind waste and pump it to a tank located away from the toilet.
If your RV has a gravity toilet now, a gravity replacement like the Dometic 400 series is the simplest swap, because it uses the same floor flange over the tank. Changing to a different type usually means changing tanks or plumbing.
Black tank habits that protect the toilet
Keep some water in the bowl and tank so waste does not dry onto the tank floor, and dump the black tank before the gray tank so gray water rinses the hose. Many RVers add a tank treatment; use one the toilet and tank makers say is safe for seals.
If the toilet smells when you flush, check that the ball seal is holding water and that the black tank vent on the roof is clear. A worn flange seal under the toilet can also leak odor; replace it whenever the toilet is removed.
Installing a new RV toilet
- Turn off the water pump and city water, and open a faucet to relieve pressure.
- Disconnect the supply line, remove the two flange nuts and lift the old toilet off.
- Clean the flange and replace the flange seal with the one supplied or specified by the maker.
- Set the new toilet over the bolts, tighten the nuts evenly and reconnect the water.
- Turn the water on, flush several times and check for leaks at the inlet and the flange.
Do not overtighten the flange nuts on a plastic base. Our RV tankless water heater guide covers another common RV plumbing upgrade.
Frequently asked questions
What size rough-in do RV toilets need?
Dometic says its 400 series fits rough-ins of 7-5/8 inches and up with a universal 2-bolt mount. Measure from the wall to the flange center.
Can I put a household toilet in an RV?
Generally no. RV toilets are gravity-flush units that drop waste into the black tank through a valve, not a trap and tank system.
Porcelain or plastic RV toilet?
Porcelain feels more residential and resists scratches; plastic is lighter. Dometic sells both in the 400 series.
Why won’t my RV toilet hold water?
The ball seal may be dirty or worn. Clean it and replace it if needed; Dometic says the 400-series seal is tool-free to replace.
How do I winterize an RV toilet?
Follow your RV maker’s winterizing steps, use RV antifreeze in the water system and flush until it reaches the bowl.
How we chose
This document-based guide makes no hands-on testing claim. We read Dometic’s product pages for the 400, 410 and 411 toilets. Thetford toilets were checked, but their maker site could not be reached and retail listings disagreed on seat height, so they are not linked; two other listings were excluded because their model and part numbers conflicted. On October 15, 2026, both linked standard new offers showed stock. Read our selection method and about Plumbing Picks.
Primary sources
- Dometic 410 Gravity Flush Toilet (dometic.com): porcelain bowl, seat height, depth, mount, rough-in, ball seal, warranty, load claims.
- Dometic 400 Gravity Flush Toilet (dometic.com): plastic bowl, mount, rough-in, warranty.
- Dometic 411 Gravity Flush Toilet (dometic.com): short porcelain version.