For an elongated bowl, pick the American Standard Champion 5321A.65CT; for a round bowl, the Champion 5320B.65CT. For a top-mount kit option, the 5503A. For a light quick-connect seat, the Cardiff.
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This guide compares four American Standard toilet seats using American Standard’s own spec sheets.
American Standard toilet seats compared (spec sheets)
On a phone, swipe or scroll the table sideways to see every column.
| Model | Shape | Length on drawing | Width | Lift-off |
|---|---|---|---|---|
| Champion 5321A.65CT | Elongated | 18-11/16 in. | 14-1/16 in. | Yes, no tools |
| Champion 5320B.65CT | Round front | 16-13/16 in. | 14-5/16 in. | Yes, no tools |
| 5503A | Elongated | 19-7/16 in. overall | 14-1/4 in. | Not listed |
| Cardiff 5257A.65MT | Elongated | 17-3/8 in. | 13-7/8 in. | Not listed |
Each sheet measures length a little differently, some from the hinge and some overall, so use the table to compare shape and features rather than to pick by a fraction of an inch. The number that decides fit is the bowl shape: elongated or round front. Our toilet seat size guide shows how to measure your bowl.
American Standard Champion 5321A.65CT: elongated, lift-off
Choose the Champion elongated for an elongated bowl if you want to take the seat off to clean. American Standard’s spec sheet (lixil.cdn.celum.cloud) lists a slow-close “No Slam” hinge, an Easy Lift Off feature for removing the seat and cover without tools, a solid plastic seat with cover, an EverClean surface and bottom-mounting hardware. It says the seat fits most conventional elongated toilets.
The drawing shows an 18-11/16-inch length, a 14-1/16-inch width and 5-1/2-inch spacing between the mounting holes. The installation sheet (lixil.cdn.celum.cloud) shows the lift-off steps: open the hinge covers, slide the seat forward off its posts, and slide it back on to reattach. It also says the hinge has built-in adjustable washers you rotate to line the seat up on the bowl, and warns not to overtighten the bolts. On October 15, 2026, the standard new offer sold by Amazon.com was in stock with model 5321A65CT.020, white.
Check American Standard Champion 5321A65CT.020 elongated toilet seat on Amazon →
American Standard Champion 5320B.65CT: round front version
Choose the Champion round front for a round bowl. The same Champion spec sheet (lixil.cdn.celum.cloud) covers the 5320B.65CT with the same slow-close hinge, tool-free lift-off, solid plastic construction and bottom-mount hardware. It lists three colors: 020 White, 021 Bone and 222 Linen.
The drawing shows a 16-13/16-inch length, a 14-5/16-inch width and 5-1/2-inch mounting-hole spacing. On October 15, 2026, the standard new offer sold by Amazon.com was in stock with model 5320B65CT.020, white.
Check American Standard Champion 5320B65CT.020 round toilet seat on Amazon →
American Standard 5503A: the newest sheet, with a top-mount kit
Choose the 5503A for an elongated bowl if you may need top mounting later. American Standard’s spec sheet (lixil.cdn.celum.cloud), dated February 2026, lists a slow-close seat and lid, solid plastic construction, bottom-mounting hardware and a 3.7-pound weight for the elongated seat. It lists a bottom mounting kit (760225-100.0070A) and a top mounting kit (760357-100.0070A) as replacement parts.
The drawing shows a 19-7/16-inch overall length, a 14-1/4-inch width and a 12-inch opening. The sheet also covers the 5503B round front seat, which weighs 3.4 pounds, with a 17-3/8-inch overall length, a 14-3/16-inch width and a 10-1/2-inch opening. Top mounting matters on toilets where you cannot reach the nuts under the bowl, such as some one-piece and skirted models. Amazon titles this listing “Transitional”; the American Standard sheet calls it the 5503A Slow Close Toilet Seat. On October 15, 2026, the standard new offer sold by Amazon.com was in stock with model 5503A00B.020, white.
Check American Standard 5503A00B.020 slow close elongated toilet seat on Amazon →
American Standard Cardiff 5257A.65MT: lightest, quick-connect nut
Choose the Cardiff for an elongated bowl if you want quick bottom-mount hardware. American Standard’s spec sheet (lixil.cdn.celum.cloud) lists a slow-close seat and lid, an EverClean surface, bottom-mounting hardware with a Quick Connect Nut, solid polypropylene plastic and a 3.31-pound weight. It says the seat fits most elongated toilets and lists a top mounting kit (760227-100.0070A) as a replacement part.
The drawing shows a 17-3/8-inch length, a 13-7/8-inch width, an 11-7/8-inch opening and 5-1/2-inch mounting-hole spacing. The same sheet covers a round front version, the 5259B.65MT, which weighs 2.82 pounds. On October 15, 2026, the standard new offer sold by Amazon.com showed a delivery date and an add-to-cart button with model 5257A65MT.020, white.
Check American Standard Cardiff 5257A65MT.020 elongated toilet seat on Amazon →
What EverClean means, in American Standard’s words
The Champion and Cardiff sheets list an EverClean surface. The Cardiff sheet explains it: the surface “inhibits the growth of stain and odor causing bacteria, mold, and mildew on the surface,” and it “does not protect against disease causing bacteria.” Treat it as an easier-to-keep-clean surface, not a health feature. You still need to clean the seat.
Slow-close, lift-off and mounting: what to look for
Slow-close. All four sheets list a slow-close seat. The lid lowers on its own instead of slamming.
Lift-off. Only the Champion sheet lists a tool-free lift-off feature. Taking the seat off makes it easier to clean the hinge area and the top of the bowl.
Bottom versus top mount. All four come with bottom-mount hardware, where nuts thread on under the bowl. If your toilet has no room to reach under the hinge holes, check for a top-mount kit; the 5503A and Cardiff sheets list one as a replacement part.
Hole spacing. The drawings for the Champion and Cardiff show 5-1/2 inches between the mounting holes, the common spacing on North American toilets. Measure yours if you are unsure.
Colors. Each sheet lists white, bone and linen options; the .020 suffix is white.
Check these before you order
- Bowl shape. Elongated or round front; measure from the bolt holes to the front rim.
- Hole spacing. 5-1/2 inches on the drawings that show it.
- Mounting. Bottom-mount hardware is included; check top-mount kits for one-piece toilets.
- Lift-off. Only the Champion lists tool-free removal.
- Color. Match the color suffix to your toilet; .020 is white on all four listings here.
- Brand fit. American Standard says these fit most conventional toilets, not only its own.
Which American Standard toilet seat should you buy?
For an elongated bowl and easy cleaning, the Champion 5321A.65CT. For a round bowl, the Champion 5320B.65CT. For an elongated seat with a top-mount kit available, the 5503A. For a lighter seat with a quick-connect nut, the Cardiff 5257A.65MT. For other brands, see our toilet seat guide, and for the toilets themselves, our American Standard toilet guide.
Frequently asked questions
Do American Standard toilet seats fit other toilets?
The Champion and Cardiff sheets say they fit most conventional elongated or round front toilets.
How do you remove an American Standard Champion seat?
Open the hinge covers and slide the seat forward off its posts; no tools are needed, per the installation sheet.
Is the American Standard toilet seat slow close?
All four seats here are slow-close.
What does EverClean do?
American Standard says it inhibits stain and odor causing bacteria, mold and mildew on the surface, but does not protect against disease causing bacteria.
Can American Standard seats be top mounted?
The 5503A and Cardiff sheets list top mounting kits as replacement parts.
How we chose
This document-based guide makes no hands-on testing claim. We read and rendered American Standard spec sheets for the Champion 5321A/5320B, the 5503A and the Cardiff 5257A, and the Champion installation sheet. On October 15, 2026, we checked each linked standard new Amazon offer for model, seller, stock and an add-to-cart button. Read our selection method and about Plumbing Picks.
Primary sources
- AS Champion seat spec sheet (lixil.cdn.celum.cloud): lift-off, drawings.
- AS Champion seat installation sheet (lixil.cdn.celum.cloud): lift-off steps.
- AS 5503A/B spec sheet (lixil.cdn.celum.cloud): 3.7 lb, top-mount kit.
- AS Cardiff spec sheet (lixil.cdn.celum.cloud): Quick Connect Nut, EverClean limit.