Can a wall-mounted toilet go in a 2x4 wall?

Yes, with the right carrier. Swiss Madison’s SM-WC424 is built for 2x4 studs. TOTO’s DuoFit installs in a 2x6 wall as shipped and in a 2x4 wall with TOTO’s THU343 outlet kit, sold separately. Swiss Madison’s SM-WC426 and TOTO’s standard outlet need a 2x6 wall.

Best Wall Mounted Toilets: Wall-Hung Toilet Kits (2026)

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Quick answer from a licensed plumber: For most bathrooms, buy the TOTO AP CWT426CMFG system. One listing has the bowl, the DuoFit in-wall tank and carrier rated to 880 lb, and the push plate; only the seat is extra. It fits a 2×6 wall as shipped, or a 2×4 wall with TOTO’s THU343 outlet kit. For a standard 2×4 wall with no add-on kit, get the Swiss Madison SM-WC424 and Ivy bundle, and add a Swiss Madison flush plate; confirm its flush volume first if your area requires 1.28 gpf. Check every listing for “bowl only” before you order.

Our pick for most bathrooms: the TOTO AP CWT426CMFG, with the bowl, in-wall tank and push plate in one kit. Check the TOTO AP CWT426CMFG system on Amazon

A wall mounted toilet, also sold as a wall-hung toilet, has no base on the floor. The bowl bolts to a steel carrier inside the wall, the tank sits in the wall behind it, and you flush with buttons on a plate. The drain leaves the back of the bowl into the wall. That leaves the floor clear for cleaning, lets you set the bowl height, and saves floor space. TOTO says its kits save up to 9 or 10 in. The trade-off is the wall. It has to be opened, framed to hold the load, and plumbed for a wall outlet. The mistake to avoid is in the box: many wall-hung listings are a bowl only, or a carrier without a flush plate. Every pick below says exactly what is in the box, per the maker.

Wall Mounted Toilets Compared

Kit	In the box (per maker)	Still to buy	Wall framing	Carrier rating (maker)	Flush (maker)
TOTO AP CWT426CMFG	Elongated bowl, DuoFit tank and carrier, push plate	Seat	2×6; 2×4 with THU343 kit	880 lb	1.28 / 0.9 gpf
TOTO RP CWT447247CMFG	D-shape bowl, DuoFit tank and carrier, seat, push plate	Framing and drain fittings only	2×6; 2×4 with THU343 kit	880 lb	1.28 / 0.9 gpf
Swiss Madison SM-WC424 + Ivy	2×4 carrier and tank, elongated bowl, seat	Flush plate	2×4	500 lb	0.8 / 1.6 (Swiss Madison); listing says 0.8 / 1.28
Swiss Madison St. Tropez + SM-WC426	2×6 carrier and tank, round bowl, seat	Flush plate	2×6	500 lb (St. Tropez page)	0.8 / 1.6 (Swiss Madison); listing says 0.8 / 1.28
TOTO RP Compact CT427CFG	Bowl only	WT172M tank, push plate, SS227 seat	2×6; 2×4 with THU343 kit	880 lb (WT172M)	1.28 / 0.9 gpf

From the TOTO and Swiss Madison documents listed below, read on September 30, 2026. Every linked listing was sold by Amazon.com and in stock that day.

System, Carrier or Bowl Only: What You Are Buying

Wall mount toilet listings come in four kinds, and the titles do not always make it clear which one you are looking at.

Complete system. Bowl, in-wall tank and carrier, and flush plate, sometimes with the seat. TOTO’s CWT kits are this kind. The AP kit leaves out the seat, and the RP kit includes it.
Carrier plus bowl bundle. Swiss Madison’s bundles pair a carrier and a bowl with a seat. The flush plate is a separate part.
Carrier or in-wall tank only. TOTO’s WT172M and Swiss Madison’s SM-WC424 and SM-WC426 on their own. Swiss Madison’s carrier sheets say the bowl and plate are sold separately, and TOTO’s WT172M sheet says the same about the plate.
Bowl only. The china alone, like TOTO’s CT427CFG. It only works on the carrier its maker names.

Plumber’s note: stay inside one brand for the bowl, carrier and plate. The inlet and outlet pipes, mounting studs and plate push rods are sized to that maker’s carrier and bowl. TOTO’s and Swiss Madison’s instructions both have you cut the inlet and outlet pipes to length from the finished wall.

What the Wall Needs

2×4 or 2×6 framing

Measure the stud depth before you pick a carrier. Swiss Madison makes the SM-WC424 for 2×4 studs and the SM-WC426 for 2×6 studs. TOTO’s DuoFit installs in a 2×6 wall as shipped, with a 2×6 outlet in the box. TOTO says a 2×4 residential wall works with its THU343 outlet kit, sold separately. TOTO’s drawings list a finished wall 1/2 to 2 in. thick over the frame. Plumber’s note: most interior walls in a house are 2×4, and a 2×6 plumbing wall gives more room for the drain. Matching the carrier to the wall you have is usually less work than building the wall out for a deeper carrier.

Carrier weight rating and bracing

The carrier holds everything, so the rating matters. TOTO rates the DuoFit to 880 lb and says the framing should support 880 lb “without damage to the wall.” Swiss Madison lists 500 lb for the SM-WC424. TOTO’s manual frames the opening with doubled king and jack studs and a doubled header, and it says to confirm the opening is square. The carrier screws to the jack studs and to the subfloor; TOTO says to use anchors in concrete. For metal studs, TOTO calls for rigid bracing so the wall does not flex and crack as someone sits and stands. Swiss Madison’s manual says to screw the carrier flush across the front of the framing.

The drain: rough-in for a wall outlet

A wall-hung bowl drains back into the carrier, and the carrier’s elbow takes the waste down or sideways inside the wall. TOTO’s manual covers a vertical drain through the floor and a left or right drain. For the vertical drain, it calls for a 3-3/4 in. hole in the subfloor 1-3/4 in. from the front of the studs. TOTO’s 2×6 drawing puts the drain center 1-3/4 or 3-1/4 in. from the front of the frame. Swiss Madison’s SM-WC424 manual also allows a vertical or offset drain and calls for a 4×3 or 3×3 mechanical coupling (not included) to the sewer line. Plumber’s note: moving a floor toilet’s drain into the wall means cutting the floor and rerouting the waste and vent piping. That needs a permit in most places. See toilet rough-in size for how floor rough-ins are measured.

Bowl height

The carrier legs set the height, and you choose it before the wall closes. TOTO lists a 15 to 19 in. mounting height for the DuoFit. Its manual has a table that matches the carrier setting to the finished rim height, measured from the finished floor. Swiss Madison says to adjust the carrier legs to the height you want but publishes no bowl-height range in the pages and sheets we read; its SM-WC424 sheet shows the frame itself adjusting from 46.5 to 51 in. tall. For the chair-height question, see comfort height vs standard toilet. Plumber’s note: set the height for the main user, and measure from the finished floor, not the subfloor.

Flush plate and access for service

The flush plate is the only door into the tank. TOTO’s manual has you cut an 8-7/8 x 5-9/16 in. opening for the plate. The flush valve, fill valve, water level and fill valve filter are all serviced through it. Swiss Madison says its removable actuator plate gives access to the plumbing too. Plates are brand specific. TOTO’s kit sheets pair the WT172M with the YT930 plate, and its standalone WT172M sheet lists the YT970 plates. Swiss Madison’s Ivy sheet lists its SM-WC001, SM-WC002 and SM-WC003 plates for both the SM-WC424 and SM-WC426 carriers. Plumber’s note: plan the plate where a hand can reach it. Do not bury it behind a shelf, a cabinet or a mirror.

Water supply and pressure

TOTO’s DuoFit uses a 1/2 in. NPT supply inside the wall, with an 8 psi minimum. Its spec sheet lists 108.75 psi maximum static pressure, but its warranty notes that product codes allow a maximum of 80 psi. Swiss Madison’s manual says to bleed the air from the lines first, because trapped air can damage the flush system. TOTO’s manual gives the same warning. TOTO’s WT172M is pre-plumbed for a WASHLET connection, and its manual’s framing drawing shows an optional GFCI outlet beside the carrier, so decide on a bidet seat before the wall closes. Plumber’s note: if your house pressure runs over 80 psi, put a pressure-reducing valve on the service before you hide a tank in the wall. TOTO’s service steps start by closing the shutoff valve in the tank, so ask the installer to show you where it is.

Top Pick: Complete TOTO System

TOTO AP CWT426CMFG Wall-Hung Toilet and DuoFit In-Wall Tank

In the box, per TOTO: CT426CFG elongated bowl + WT172M DuoFit in-wall tank and carrier + YT930 round push plate · seat sold separately · 1.28 / 0.9 gpf dual flush · carrier rated to 880 lb · 2×6 wall as shipped; 2×4 with TOTO’s THU343 outlet kit · bowl height adjusts 15 to 19 in. · one-year limited warranty

This is the easiest way to buy a wall-hung toilet without guessing at part numbers. TOTO’s spec sheet lists three key components: the CT426CFG bowl, the WT172M in-wall tank system and the YT930 push plate. The seat is not in the kit. TOTO’s product page says “Seat sold separately,” and the sheet lists the SS114 SoftClose seat as an option. The bowl is elongated, with TOTO’s CEFIONTECT glaze and its Dynamax Tornado flush. The flush is 1.28 or 0.9 gallons, which TOTO averages at 1.03 gpf.

The carrier is the part a plumber looks at first. TOTO rates the DuoFit system to support up to 880 lb and says the framing around it should carry that load too. It installs in a 2×6 wall as shipped. TOTO says a 2×4 residential wall works “with waste outlet kit,” and its WT172M sheet lists that kit, the THU343, as sold separately. TOTO’s drawing puts the bowl 21-1/4 in. out from the finished wall and lists a finished wall 1/2 to 2 in. thick over the frame. Bowl height is set by the carrier legs, from 15 to 19 in.

Bowl, in-wall tank and push plate under one listing, per TOTO
Carrier rated to 880 lb, per TOTO
Bowl height adjusts 15 to 19 in.
Elongated bowl with a 1.28 / 0.9 gpf dual flush

Seat sold separately
2×4 walls need the THU343 outlet kit, sold separately
One-year limited warranty on bowl and tank, per TOTO
Needs an open wall and framing work

Verdict: The wall-hung toilet to buy for most remodels: one TOTO listing covers the bowl, carrier and plate, so only the seat is left to order.

Check the TOTO AP CWT426CMFG system on Amazon

Most Complete: Seat Included

TOTO RP CWT447247CMFG Wall-Hung D-Shape Toilet and DuoFit Tank

In the box, per TOTO: CT447CFG D-shape bowl + WT172M DuoFit in-wall tank + SS247 slim SoftClose seat + YT930 push plate · 1.28 / 0.9 gpf dual flush · carrier rated to 880 lb · 2×6 wall as shipped; 2×4 with the THU343 outlet kit · bowl height adjusts 15 to 19 in. · matte silver plate on the linked listing

TOTO’s RP kit is the same DuoFit carrier and tank as the AP pick, with a D-shape bowl and the seat in the box. TOTO’s spec sheet lists four kit components: the CT447CFG bowl, the WT172M tank system, the SS247 slim D-shape SoftClose seat and the YT930 push plate. That makes it the one pick here where nothing but the framing and drain fittings is left to buy. The linked listing has the matte silver plate.

The carrier specs match the AP kit, per TOTO: 1.28 or 0.9 gpf, an adjustable 15 to 19 in. mounting height, up to 880 lb of support, and a 2×6 wall unless you add the THU343 2×4 outlet kit. TOTO says this kit saves up to 9 in. of floor space compared with a standard floor-mounted toilet. Plumber’s note: a D-shape bowl takes a D-shape seat, so order TOTO’s SS247 if the seat ever needs replacing.

Bowl, tank, seat and push plate in one kit, per TOTO
Saves up to 9 in. of floor space, per TOTO
Same 880 lb DuoFit carrier as the AP kit
SoftClose seat with quick-release hinges, per TOTO

D-shape bowl takes TOTO’s matching seat only
2×4 walls need the THU343 outlet kit, sold separately
One-year limited warranty, per TOTO
Needs an open wall and framing work

Verdict: The pick when you want every visible part in one box and like the squarer D-shape bowl.

Check the TOTO RP CWT447247CMFG system on Amazon

Best for a 2×4 Wall

Swiss Madison SM-WC424 Carrier and SM-WT450 Ivy Wall-Hung Toilet Bundle

In the box: SM-WC424 Fantome M 2×4 carrier and tank + SM-WT450 Ivy elongated bowl with quick-release seat · flush actuator plate sold separately · carrier rated to 500 lb, per Swiss Madison · fits 2×4 studs · carrier legs set the bowl height (no range published) · flush 0.8 / 1.6 gpf per Swiss Madison’s Ivy page; the Amazon listing says 0.8 / 1.28 · one-year limited warranty (three years only if bought and registered at swissmadison.com)

If the wall is standard 2×4 framing and you do not want to add an outlet kit, this is the bundle. Swiss Madison builds the SM-WC424 carrier for 2×4 studs and lists a 500 lb weight capacity. Its spec sheet says the wall-hung bowl and the flush actuator plate are sold separately, and the Ivy sheet names the plates that fit: SM-WC001, SM-WC002 or SM-WC003. This bundle covers the bowl, so the plate is the one part to add. The SM-WC001W is the white version of that plate, sold by Amazon. The Ivy bowl comes with a quick-release seat, per Swiss Madison.

Check the flush volume before you buy if your area requires 1.28 gpf. Swiss Madison’s own Ivy bowl page lists 0.8 or 1.6 gallons. The Amazon listing for this bundle says 0.8 or 1.28, and Swiss Madison’s carrier documents give no figure. Plan on 1.6 gpf unless Swiss Madison confirms 1.28 in writing. Swiss Madison’s SM-WC424 manual says the drain can run straight down or be offset left or right. To tie into the sewer line it calls for a 4×3 or 3×3 mechanical coupling, depending on the install, and the coupling is not included. The manual also says to avoid outside walls because the tank can freeze. Swiss Madison recommends a licensed installer.

Built for 2×4 studs with no extra outlet kit
Carrier rated to 500 lb, per Swiss Madison
Seat included with the bowl
Drain can run down or offset left or right, per the manual

Flush plate sold separately
Swiss Madison lists a 1.6 gpf full flush; the listing says 1.28
No code listing in the Swiss Madison documents we read
Lower carrier rating than TOTO’s 880 lb

Verdict: The pick for a 2×4 wall: carrier, bowl and seat in one listing, plus a Swiss Madison plate.

Check the Swiss Madison SM-WC424 + Ivy bundle on Amazon

Check the SM-WC001W flush plate on Amazon

Best for a 2×6 Wall, Round Bowl

Swiss Madison SM-WT449 St. Tropez Wall-Hung Toilet and SM-WC426 Carrier

In the box: SM-WT449 St. Tropez round bowl with soft-close seat + SM-WC426 2×6 carrier and tank · flush actuator plate sold separately · fits 2×6 studs · 500 lb weight capacity on the St. Tropez page · flush 0.8 / 1.6 gpf per Swiss Madison’s St. Tropez page; the Amazon listing says 0.8 / 1.28 · one-year limited warranty (three years only if bought and registered at swissmadison.com)

This bundle pairs Swiss Madison’s round St. Tropez bowl with the SM-WC426 carrier, which Swiss Madison makes for 2×6 studs. The St. Tropez spec sheet lists a soft-close seat and mounting hardware in the bowl box. Both Swiss Madison carrier sheets list the flush actuator plate as sold separately, and Swiss Madison’s Ivy sheet lists its SM-WC001 to SM-WC003 plates for the SM-WC426 carrier. Add the same SM-WC001W plate or another of those plates. Swiss Madison’s St. Tropez page lists a 500 lb weight capacity.

The SM-WC426 manual has a wallboard note worth reading before the wall closes. It recommends cement board or tile backer over the carrier and says to avoid gypsum board because it “may compromise the load strength” of the install. TOTO’s manual, by contrast, recommends a minimum of 1/2 in. drywall. Follow the sheet for the carrier you buy. The flush volume has the same conflict as the Ivy bundle: Swiss Madison’s St. Tropez page lists 0.8 or 1.6 gallons, and the Amazon listing says 0.8 or 1.28. Plan on 1.6 unless Swiss Madison confirms otherwise. Swiss Madison’s spec sheet lists the round St. Tropez bowl at 19.5 in. deep; the elongated Ivy sheet lists 20-11/16 in.

2×6 carrier and bowl in one listing
Soft-close seat included with the bowl
Round bowl, 19.5 in. deep per Swiss Madison
Same Swiss Madison plates fit as the Ivy bundle

Flush plate sold separately
Swiss Madison lists a 1.6 gpf full flush; the listing says 1.28
Manual recommends cement board or tile backer, not gypsum board
No code listing in the Swiss Madison documents we read

Verdict: The pick for a 2×6 wall or a plumbing wall that is already deep, when you want a round bowl.

Check the Swiss Madison St. Tropez + SM-WC426 bundle on Amazon

Most Compact: Bowl Only

TOTO RP Compact CT427CFG Wall-Hung Bowl (with WT172M Tank)

Bowl only: CT427CFG D-shape compact bowl · needs the WT172M DuoFit in-wall tank, a push plate and the SS227 seat, each sold separately · 490 mm (about 19-5/16 in., our arithmetic) from wall to front of bowl, per TOTO · saves up to 10 in. of floor space, per TOTO · 1.28 / 0.9 gpf with the WT172M

This is the shortest bowl here. TOTO’s RP Compact sheet says it saves up to 10 in. of floor space compared with a standard floor-mounted toilet and puts the front of the bowl 490 mm from the wall. That is about 19-5/16 in. (our arithmetic). It is the right fit for a powder room where the door swing or a vanity is the problem. The catch is that this listing is the bowl only. Its Amazon title says “elongated”; TOTO’s sheet calls it a D-shape bowl, which is why it takes the SS227 seat. TOTO sells it as part of the CWT427227CMFG kit, and that sheet names the other parts: the WT172M in-wall tank, the SS227 slim D-shape SoftClose seat and a YT930 push plate.

So you buy it in pieces: the bowl, the TOTO WT172M DuoFit tank, a TOTO YT930 push plate and the SS227 seat. TOTO’s WT172M sheet lists the push plate as sold separately, and the RP Compact kit sheet names the YT930 as the plate for this bowl and tank. One paperwork quirk: TOTO’s standalone WT172M sheet lists only the CT447CFG, CT449CFG and CT437FG bowls, but TOTO’s RP Compact kit sheet pairs the CT427CFG with the WT172M. Go by the kit sheet, and keep the part numbers together when you order.

490 mm from wall to front of bowl, per TOTO
Saves up to 10 in. of floor space, per TOTO
Uses the same 880 lb DuoFit carrier
Pick your own push plate finish

Bowl only: tank, plate and seat are separate purchases
Four part numbers to match
D-shape bowl takes TOTO’s SS227 seat
TOTO’s WT172M sheet does not list this bowl

Verdict: The pick for the tightest room, if you are willing to order the bowl, tank, plate and seat as four separate parts.

Check the TOTO CT427CFG compact bowl on Amazon

Check the TOTO WT172M in-wall tank on Amazon

I send an occasional note when a new guide goes up — repairs worth doing yourself, and the parts that actually last. No spam, no course funnel; written by a licensed Georgia plumber.

Rear-Outlet (Back-Outlet) Floor Toilets

A rear-outlet toilet, also called a back-outlet or rear-discharge toilet, is a different thing from a wall-hung one. It sits on the floor with a normal tank, but its drain leaves the back of the bowl into a pipe in the wall. It is used in basements and remodels where the drain comes through the wall and the floor cannot be cut. MaceratingFlo’s R8 is one. Its spec sheet calls it a floor-mounted, 1.28 gpf, P-trap two-piece toilet with a wall waste outlet. Its manual says the center of the wall drain must be about 7 in. above the finished floor, with the pipe sticking out about 0.4 to 0.5 in. past the finished wall. It also calls for at least 35 psi of supply pressure. MaceratingFlo says it connects to the waste pipe with the included extension pipe and needs no macerator pump.

We did not link one. MaceratingFlo’s R8 documents list no plumbing code certification, such as cUPC or ASME A112.19.2, and the Amazon listings we read (models MF00R8-A and MFR8-B) do not exactly match the maker’s MF000R8 sheet. Plumber’s note: if a rear-outlet floor toilet is the plan, ask the maker for its certification listing and measure the drain height before you order. If there is no drain at the right height, an upflush system pumps to one; see upflush toilets for a basement bathroom.

Before You Buy

Measure the studs. 2×4 (3-1/2 in.) or 2×6 (5-1/2 in.). Match the carrier, or plan on TOTO’s THU343 kit for a 2×4 wall.
Read the box contents. Note whether the listing has the bowl, carrier, plate and seat. Write down what is missing and order it with the toilet.
Find the drain. Know whether the waste will drop through the floor inside the wall or run sideways, and whether you need a 3 in. or 4 in. connection.
Check the flush volume. If your area requires 1.28 gpf or less, get Swiss Madison’s answer in writing before you order: its bowl pages list a 1.6 gpf full flush, and the Amazon listings say 1.28. TOTO lists 1.28 / 0.9 gpf for all three TOTO picks.
Ask for the code listing if the job is permitted. TOTO’s sheets say the bowl meets ASME A112.19.2 and the carrier ASME A112.6.2, and list IAPMO (cUPC) certification. The Swiss Madison pages and sheets we read list no certification, and its warranty says it makes no warranty that its products meet local building or plumbing codes. Ask Swiss Madison for its listing before you order.
Plan access. Keep the flush plate where it can be removed later.

Installing a Wall-Hung Toilet

Order of work

The carrier goes in with the wall open. Frame the opening, set the carrier height, and screw it to the framing and floor. Then connect the drain and the supply and check for leaks. Both makers ship mud guards, or roughing covers, to keep debris out of the tank and pipes while the wall is finished. TOTO’s manual has you cut the drywall for a 4-1/2 in. drain hole, a 2-1/2 in. inlet hole, two 3/4 in. stud holes and the plate opening. Then you cut the inlet and flange pipes to length from the finished wall and hang the bowl. TOTO’s drawing shows the back of the bowl tight to the finished wall, about a 1/16 in. gap, and marks a baseboard behind the bowl as an improper install. Plumber’s note: keep baseboard and tile trim out of the bowl’s footprint so the bowl sits flat on the wall. Swiss Madison’s manual says to keep the threads on the mounting bolts covered and clean until the bowl is hung.

When to call a pro

Swiss Madison recommends a licensed professional for all of its installs. Plumber’s note: this is framing, drain, vent and supply work inside a wall. In most places that means a permit and an inspection, and the drain change is the hard part. A licensed plumber can rough in the carrier and drain while the wall is open. Hanging the bowl and plate after the tile is done is the easy end of the job. If you are only replacing a floor toilet, see how to replace a toilet.

FAQ

Do wall-hung toilets come with the carrier?

Sometimes. Read the listing and the maker’s sheet. TOTO’s CWT426CMFG and CWT447247CMFG kits include the WT172M in-wall tank and carrier and a push plate. Swiss Madison’s bundles include the carrier and bowl but not the flush plate. A listing that says “bowl only,” like TOTO’s CT427CFG, needs the carrier, plate and seat bought separately. A wall-hung bowl cannot be installed without a carrier.

Can a wall-mounted toilet go in a 2×4 wall?

Yes, with the right carrier. Swiss Madison’s SM-WC424 is built for 2×4 studs. TOTO’s DuoFit installs in a 2×6 wall as shipped and in a 2×4 wall with TOTO’s THU343 outlet kit, sold separately. Swiss Madison’s SM-WC426 and TOTO’s standard outlet need a 2×6 wall.

How much weight can a wall-hung toilet hold?

The rating belongs to the carrier and the framing around it. TOTO rates its DuoFit system to 880 lb and says the framing must carry that load without damage to the wall. Swiss Madison lists 500 lb for its SM-WC424 carrier. TOTO’s manual calls for doubled king and jack studs and a doubled header around the carrier. For metal studs, it calls for rigid bracing so the wall does not flex.

How do you fix a wall-hung toilet tank inside the wall?

Through the flush plate opening. TOTO’s manual shows the flush valve and fill valve coming out through that opening after you remove the plate, the splash guard and the actuator. The water level and fill valve filter are serviced the same way. Swiss Madison also lists the removable actuator plate as the access point. Plumber’s note: keep the plate reachable. Do not tile a vanity or shelf over it.

Is a rear-outlet toilet the same as a wall-hung toilet?

No. Both drain back into the wall, but they are built differently. A wall-hung toilet hangs off a carrier with the tank hidden in the wall. A rear-outlet (back-outlet) floor toilet sits on the floor with a visible tank, and its drain leaves the back of the bowl into a pipe in the wall. MaceratingFlo’s R8 manual, for example, puts that wall drain about 7 in. above the finished floor. If there is no drain at the right height, see upflush toilet vs sewage ejector pump.

Why Trust Plumbing Picks

Plumbing Picks is written by a licensed Georgia journeyman plumber. Every spec here comes from the maker documents listed below or the Amazon listings we link; nothing comes from hands-on testing. On September 30, 2026, every linked listing was sold by Amazon.com and in stock. If you buy through a link we may earn a commission at no extra cost to you. Nobody pays to be included here. More on who writes this and how we pick.

Sources

TOTO: CWT426CMFG AP Wall-Hung Toilet spec sheet SS-01515, CWT426CMFG product page
TOTO: CWT447247CMFG RP Wall-Hung Toilet spec sheet SS-01338, CWT447247CMFG product page
TOTO: CWT427227CMFG RP Compact Wall-Hung Toilet spec sheet SS-01829 (CT427CFG bowl)
TOTO: WT172M DuoFit In-Wall Tank Unit spec sheet SS-01413, WT172M parts manual PD-01107, DuoFit WT171M/WT172M installation and owner’s manual
Swiss Madison: Fantome M SM-WC424 2×4 carrier product page, SM-WC424 spec sheet, SM-WC424 installation instructions
Swiss Madison: Fantome M SM-WC426 2×6 carrier product page, SM-WC426 spec sheet, SM-WC426 installation instructions
Swiss Madison: Ivy SM-WT450 wall-hung bowl product page, Ivy spec sheet, St. Tropez SM-WT449 wall-hung bowl product page, St. Tropez spec sheet, Swiss Madison warranty (2026)
MaceratingFlo: R8 rear discharge two-piece toilet product page, MF000R8 specification sheet, R8 installation instructions
Amazon listings for the TOTO CWT426CMFG#WH, TOTO CWT447247CMFG#MS, Swiss Madison SM-WC424 + SM-WT450 bundle, Swiss Madison SM-WT449 + SM-WC426 bundle, TOTO CT427CFG#01, TOTO WT172M, TOTO YT930#WH and Swiss Madison SM-WC001W (linked above), plus the MaceratingFlo rear-outlet listings we checked but did not link

Bottom Line

A wall-hung toilet is a carrier job first and a toilet second. Buy the TOTO AP CWT426CMFG for a complete system on TOTO’s 880 lb carrier, with only the seat to add. Choose the TOTO RP CWT447247CMFG if you want the seat in the box too. The Swiss Madison SM-WC424 and Ivy bundle fits a 2×4 wall without an add-on kit, and the St. Tropez and SM-WC426 bundle suits a 2×6 wall. The TOTO CT427CFG is the most compact bowl, sold as a bowl only. Match the carrier to the studs, frame for the load, and keep the flush plate where you can reach it.