The One That Clears in a Single Flush, Sized to Your Rough-In, So the Bowl Never Comes Over the Rim
5 picks compared · prices, ratings and stock checked October 13, 2026
Our Top Pick
For most 12 in rough-in bathrooms, the HOROW T0338W One Piece Toilet (dual flush 1.1/1.6 GPF, 2 in fully glazed trapway, 17.3 in seat), which is also sold in a 10 in rough-in version. If you want a full 1.6 gallon flush from a long-established brand, the TOTO Drake CST776CSFG Two-Piece. Measure your rough-in before ordering either.
4.5 on Amazon · 1,014 ratings
Quick answer
The best toilet for most homes is a 12 in rough-in, elongated, chair-height model with a fully glazed trapway of 2 in or more, and the HOROW T0338W One Piece Toilet (1.1/1.6 GPF dual flush, 2 in trapway, 17.3 in seat) leads this page, rated 4.5 stars across 1,014 Amazon ratings. If you want the full 1.6 gallon flush, buy the TOTO Drake CST776CSFG Two-Piece. If your bolts sit 10 in from the wall, HOROW's 10 in version fits where the others will not. A toilet that clears in one flush is the toilet that does not overflow, and no new bowl fixes a blocked drain line.
Every pick below is currently stocked — ratings and stock read from Amazon on 13 October 2026.
Best for: A standard or 10 in rough-in bathroom that needs a compact, chair-height one-piece with a stated trapway size
Listing verified 13 Oct 2026
Best for: A busy family bathroom where one strong 1.6 gallon flush matters more than water savings
Listing verified 13 Oct 2026
Best for: A 12 in rough-in bathroom where a published flush score matters and a one-piece is preferred
Listing verified 13 Oct 2026
Best for: A 12 in rough-in bathroom that wants a 1.28 gallon single flush and a stated flush score
Listing verified 13 Oct 2026
Best for: A household that wants a one-piece at standard seat height, with room for a 28.75 in deep bowl
Listing verified 13 Oct 2026
How this page was made: we compare the current Amazon listings, the makers' published specs and what verified buyers report, then rank by fit for the job. Ratings, review counts and stock are read from Amazon and dated. We earn a commission on purchases through our links; it does not change the order. Reviewed by Marcus Reed, IICRC-certified Water Restoration Technician.
Full Reviews
Each pick in detail: what the listing states, what buyers report, and where it falls short.
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Listing verified 13 Oct 2026
See it on Amazon ↗Best Overall
Quick Verdict
HOROW T0338W One Piece Toilet: a stated 2 in glazed trapway and a 10 in or 12 in rough-in choice, with no MaP score published.
Key Specs
Type
One-piece, elongated bowl
Flush (stated)
Siphon flush, dual flush 1.1/1.6 GPF
Trapway (stated)
Fully glazed, 2 in
MaP flush score
Not stated on this listing
Seat height (stated)
17.3 in floor to seat, ADA chair height
Rough-in (stated)
10 in and 12 in versions offered
Pros
Cons
Suited to
A standard or 10 in rough-in bathroom that needs a compact, chair-height one-piece with a stated trapway size
Our take
HOROW's listing gives two of the numbers that matter for a clean clear and that most toilet listings skip: a fully glazed trapway of 2 in and a siphon flush with 1.6 gallons behind the full setting. What it does not give is a MaP score, so treat the clearing power as a maker's claim backed by a large buyer record rather than a published test figure. The 10 in rough-in version is the practical reason to put this toilet first. Older homes often have the drain centered 10 in from the wall, and a 12 in toilet will not fit there. Measure from the finished wall to the center of the bolt caps before you order, and pick the matching version. The 1.1 gallon light flush saves water day to day, but the 1.6 gallon full flush sits above the current WaterSense limit.
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Listing verified 13 Oct 2026
See it on Amazon ↗Best Two-Piece Flush
Quick Verdict
TOTO Drake CST776CSFG Two-Piece: a 3 in flush valve and a full 1.6 gallon flush, with the seat, wax ring and supply line bought separately.
Key Specs
Type
Two-piece, elongated, Universal Height
Flush (stated)
1.6 GPF Tornado Flush, siphon jet bowl, 3 in flush valve
Glaze (stated)
CEFIONTECT smooth glaze
Trap seal (as the listing words it)
2-1/8 in
Minimum water pressure (stated)
8 psi flowing
Rough-in (stated)
12 in
Pros
Cons
Suited to
A busy family bathroom where one strong 1.6 gallon flush matters more than water savings
Our take
The Drake is the pick for a household that has fought clogs and wants the full 1.6 gallons the federal standard allows, delivered through a 3 in flush valve rather than the 2 in valve on many tanks. A bigger valve lets water leave the tank faster, which is what starts the siphon in the bowl; TOTO's listing pairs that with a siphon jet and the CEFIONTECT glaze. The listing also states an 8 psi minimum flowing pressure, worth knowing if you are on a well or at the end of a long supply run. Two things to budget for: the toilet ships without a seat, a wax ring, flange bolts or a supply line, and it is not a WaterSense-level flush, so check your utility's rebate rules before choosing it over a 1.28 gallon model.
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Listing verified 13 Oct 2026
See it on Amazon ↗Best Stated Flush Score
Quick Verdict
Casta Diva Elongated One Piece Toilet: a stated MaP 1,000 g flush with the wax seal and hardware in the box, but check the WaterSense claim yourself.
Key Specs
Type
One-piece, elongated, skirted
MaP flush score (stated)
1,000 grams
Flush (stated)
Siphon jet, dual flush 1.1 GPF liquids / 1.6 GPF solids
Trapway (stated)
Fully glazed; diameter not stated
Seat height (stated)
17 in, ADA chair height
Footprint (stated)
27.17 in D x 14.37 in W x 25.39 in H
Pros
Cons
Suited to
A 12 in rough-in bathroom where a published flush score matters and a one-piece is preferred
Our take
A MaP score is the one flush figure that comes from a standard test rather than a slogan: a lab loads the bowl with soybean-paste test media and records how many grams clear in a single flush, on a scale that tops out at 1,000. Casta Diva states 1,000 grams for this toilet, which is why it ranks above picks with no score at all, though the number is the maker's claim on the listing, and MaP's own consumer tips call 500 grams and above excellent. The box includes the wax seal, bolts and seat, which cuts the parts list to a supply line. One correction to the listing: a 1.1/1.6 dual flush met the old WaterSense averaging rule, but EPA's 2024 revision requires the full flush itself to be 1.28 gallons or less.
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Listing verified 13 Oct 2026
See it on Amazon ↗Best 1.28 GPF Two-Piece
Quick Verdict
HOROW 17 in Two-Piece Elongated Toilet: 1.28 gallons, single flush, MaP 1,000 g stated; trapway size and dimensions are not on the listing.
Key Specs
Type
Two-piece, elongated
Flush (stated)
360-degree siphon flush, 1.28 GPF single flush
MaP flush score (stated)
1,000 grams
Seat height
17 in, ADA chair height, per the title
Rough-in (stated)
12 in
Trapway
Size not stated on this listing
Pros
Cons
Suited to
A 12 in rough-in bathroom that wants a 1.28 gallon single flush and a stated flush score
Our take
Single flush at 1.28 gallons is the simplest way to get water savings that hold up: there is no reduced button for a guest to press on solid waste and then flush twice. HOROW pairs that volume with a stated MaP 1,000 gram score on this two-piece, which is the combination the current WaterSense specification is built around, though the listing does not show the label itself. The gaps are physical: no trapway diameter and no outside dimensions on the listing, so download the maker's drawing before you order for a tight alcove. Two-piece toilets also carry a tank-to-bowl gasket; tighten the tank bolts evenly and look under the tank once a year for a damp ring, because a slow seep there wets the floor behind the bowl where nobody looks.
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Listing verified 13 Oct 2026
See it on Amazon ↗Best Standard-Height One-Piece
Quick Verdict
DeerValley Elongated One Piece Toilet: a standard 16 7/8 in seat and a stated MaP 800 g, in a long 28.75 in footprint.
Key Specs
Type
One-piece, elongated, skirted
Flush (stated)
Dual flush 1.1/1.6 GPF
MaP flush score (stated)
800 grams
Seat height (stated)
16 7/8 in, standard height
Footprint (stated)
28.75 in L x 14 in W x 28 in H
Rough-in (stated)
12 in
Pros
Cons
Suited to
A household that wants a one-piece at standard seat height, with room for a 28.75 in deep bowl
Our take
Chair-height bowls are everywhere in this category, and they are the wrong choice for a child's bathroom or for a shorter adult whose feet leave the floor at 17 in. DeerValley's one-piece sits at 16 7/8 in, close to the old standard, and still states a MaP score of 800 grams for its 1.6 gallon full flush. That score is below the 1,000 gram ceiling the Casta Diva states, and the listing does not give the trapway size, so for a bathroom with a clogging history the Casta Diva or the TOTO is the safer order. The number to check before buying this one is depth: 28.75 in from the wall is about 2 in longer than the HOROW T0338W, which can change whether the door clears the bowl.
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What to know before you buy.
Most toilet overflows do not start in the sewer. They start in the bowl's own trap, where a flush that did not quite clear leaves paper and waste behind, the next flush meets it, and the second push is the one that comes over the rim. A toilet that moves everything through in one go removes that first step, which is why the flush figures on a listing matter more than the shape of the tank. The limit is the drain. A new bowl cannot clear a clog past the flange, and if the tub gurgles or water rises in a shower drain when you flush, the block is in the main line and you are looking at a sewage backup, not a toilet problem. Our toilet overflow and who-to-call guides cover that case. Either way, EPA's mold guide says to dry water-damaged areas within 24 to 48 hours, so a wet bathroom floor is on a clock from the first flush.
Three numbers describe a flush. The MaP score is grams of soybean-paste test media a toilet clears in a single flush, on a scale that tops out at 1,000 grams; MaP's own consumer tips call 500 grams and above excellent. Casta Diva and the HOROW two-piece state 1,000 grams, DeerValley states 800, and the HOROW T0338W and TOTO Drake state none. Gallons per flush is water use: 1.6 is the federal maximum and WaterSense sets 1.28, which is 20 percent less. Since EPA's 2024 revision of the WaterSense specification, the full flush of a dual-flush toilet must itself be 1.28 gallons or less; under the old rule a 1.1/1.6 toilet averaged to about 1.27 and could qualify, and it no longer does. The trapway is the bend the waste travels through; fully glazed and 2 in or wider is what to look for, with a 3 in flush valve in the tank as a bonus.
Rough-in is the distance from the finished wall to the center of the drain, and you read it from the toilet you have: measure from the wall surface, not the baseboard, to the center of the bolt caps at the base. Most homes measure 12 in. Older homes often measure 10 in, and 14 in exists. A 12 in toilet will not fit a 10 in drain; a 10 in toilet fits a 12 in drain but leaves a gap behind the tank. Of the picks here only the HOROW T0338W offers a 10 in version. Then check the room. Depth on this page runs from 25.39 in to 28.75 in, which decides whether the door clears the bowl and how much knee room is left. Width runs 14 in to 15 in. If the supply stop sits close to the drain centerline, a skirted toilet can land on top of it, so note where that valve is before choosing a skirted one-piece.
Flush power comes from the bowl, the trapway and the flush valve, not from whether the tank is molded to the bowl, so pick the style on cleaning and handling. A one-piece has no tank-to-bowl gasket to seep and no seam to scrub, but it comes as one heavy box, and none of the one-piece listings here state a weight. A two-piece arrives as tank and bowl, easier for one person to carry up stairs and set over the bolts, and if the tank cracks you replace the tank. Seat height is the other choice. Chair height, 17 in to 17.3 in on this page, suits taller adults and anyone who struggles to stand from a low bowl. The DeerValley's 16 7/8 in is closer to the old standard and better for children and shorter adults. All five picks are elongated, which adds length in front of the tank; a round bowl saves that in a cramped powder room.
Every time a toilet comes off the flange it goes back on a new wax ring, and the listings differ on what is in the box: Casta Diva includes the wax seal and bolts, HOROW's two-piece says installation kit, and TOTO sells the wax ring, flange bolts and supply line separately. Buy a new braided supply line regardless, and test that the shutoff under the tank closes fully before the old toilet comes off. With the old bowl up, look at the flange. It should sit level on top of the finished floor with no cracks, and the subfloor around it should be firm. A flange below floor level, a broken flange, a soft or stained subfloor, a drain that has to move to change the rough-in, or any work your local code requires a permit for is a licensed plumber's job, as is a main-line clog that keeps coming back. Our toilet-leaking-at-base guide shows what each of those looks like.
A new toilet fixes a bowl that will not clear or a cracked, wobbling or oversized fixture. It does not fix the common failures that send people shopping. A toilet that runs or refills on its own has a worn flapper or fill valve: EPA's dye test is a few drops of food coloring in the tank, and color in the bowl after 10 minutes means the flapper is leaking. A bowl that drains slowly after years of good service often has mineral scale in the rim jets, not a weak design. A clog that a plunger or a closet auger clears is a clog, and a block that returns in every fixture is a drain-line job for a plumber. Water at the base of the bowl is a wax ring or flange problem, not a reason for a new bowl. Spend on a toilet when the flush itself is the fault, and on the part when the part is.
The toilet with a published MaP score near 1,000 grams, a fully glazed trapway of 2 in or wider and a 3 in flush valve. On this page the Casta Diva one-piece and the HOROW 17 in two-piece both state 1,000 grams, and the TOTO Drake states a 3 in valve with a full 1.6 gallon flush.
A listing that gives no score is making a claim. No toilet clears a clog that sits past the flange in the drain line; that is auger or plumber work.
Not for flushing. The bowl, trapway and flush valve set the flush, and both styles use the same designs.
A one-piece is easier to wipe down and has no tank gasket to seep; a two-piece is lighter to carry in two parts, usually offers more rough-in options and lets you replace a cracked tank alone. Choose on cleaning, carrying and what your rough-in allows, then compare the flush figures.
YesWhen it carries a flush score to prove it. WaterSense set 1.28 gallons as 20 percent less than the 1.6 gallon federal standard, and labeled toilets must clear all the test media in a single flush in at least four of five tries.
The HOROW 17 in two-piece here states 1.28 gallons with a MaP score of 1,000 grams, the same score the 1.6 gallon Casta Diva states. Compare scores, not gallons, and remember a 1.1/1.6 dual-flush no longer meets the WaterSense full-flush limit.
MaP's own consumer tips say 500 grams and above gives excellent performance, and the scale tops out at 1,000 grams. The score is the weight of soybean-paste test media a toilet clears in one flush under a standard lab test.
On this page three picks state a score, 800 grams for the DeerValley and 1,000 for the Casta Diva and the HOROW two-piece, and two state none. Treat a listing's number as the maker's claim until you find the model on MaP's public list.
Measure from the finished wall behind the toilet, not the baseboard, to the center of the bolt caps at the base of the bowl. Around 12 in is the standard most new toilets fit; around 10 in is common in older homes, and a 12 in toilet will not fit it.
If the number is not close to 10, 12 or 14, measure again from the other bolt. The HOROW T0338W is the only pick here sold in a 10 in version.
YesTo both. A wax ring seals once; lifting the bowl breaks it, so every reinstall gets a new one, and a new braided supply line beats trusting a hose of unknown age under house pressure.
Check the box first: Casta Diva's listing includes the wax seal and bolts, while TOTO's says the wax ring, flange bolts and supply line are bought separately. Our toilet supply line review covers the line, and the toilet-leaking-at-base guide shows a failed ring.
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Describe what you can see — where the water is coming from, how long it has been there, and whether it smells — the more specific you are, the faster the right company is on the line. If the source is a pipe or an appliance, shut the main water valve first. Have four things ready and the call goes quickly: the address, when the water started, what is wet now, and whether you have filed an insurance claim.
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A toilet supply line sits under full house pressure day and night, and an old plastic line that cracks at its nut keeps running until someone closes the valve. These picks are braided stainless connectors in the standard 3/8 in compression x 7/8 in ballcock size, compared on length, nut material and what each listing states, with the fitting habits and the leak sensor that matter as much as the hose.
Read the comparisonA toilet needs a plunger with a flange or beehive head, because a flat cup cannot seal in the curved outlet at the bottom of the bowl. These picks are compared on head shape, handle and storage as each listing states them, alongside the steps that stop a rising bowl from reaching the floor and the point where a toilet auger should take over.
Read the comparisonWhen a plunger fails, a toilet auger is the next tool, because its cable is built to pass through the trap cast into the porcelain without scratching the bowl. These picks are 3 ft and 6 ft closet augers compared on reach, bowl protection and drill use, with the signs that point past the toilet to the main line.
Read the comparisonA water leak detector catches a leak while it is still a puddle rather than an insurance claim. These four flood sensors and water alarms range from a standalone 110 dB alarm with no Wi-Fi to a LoRa kit that sounds on the spot and texts your phone.
Read the comparisonA toilet flapper that no longer seals lets tank water trickle into the bowl around the clock, and the fill valve quietly tops the tank up behind it. These picks are 2 in and 3 in flappers from Korky and Fluidmaster, compared on which flush valves they fit, whether the flush volume adjusts, and how the material stands up to chlorine, with the dye test that tells you whether you need one at all.
Read the comparisonThe fill valve is the part that refills the tank and, more importantly, the part that has to stop. One that sticks open runs water down the overflow tube all day, and if that tube is blocked the water comes over the rim. These picks are Fluidmaster, Korky and Kohler fill valves compared on height range, water-level adjustment, what the kit includes and which toilets each one fits, with the critical level mark and the 1 in water line explained.
Read the comparisonThe seal between the toilet and the drain flange is the one plumbing joint in the house that sits under the fixture where no one can see it fail. When it does, a little water escapes at the base on every flush and soaks the subfloor for months before the floor feels soft. These picks are wax rings and waxless seals compared on the flange heights each one covers, whether you can lift the toilet and reset it, and what each listing includes.
Read the comparison