Kohler Memoirs Classic Comfort Height K-3818 Review
A research-based review of the Kohler Memoirs Classic K-3818, a traditional two-piece, elongated, 1.6 gpf Comfort Height toilet, with its status and 1.28 gpf alternatives.
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The Kohler Memoirs Classic K-3818 is a traditional-style, two-piece, elongated toilet with a Comfort Height (chair-height) bowl and a 1.6 gallon-per-flush AquaPiston gravity flush. It belongs to Kohler’s Memoirs collection, and the “Classic” version has rounded, molded detailing meant to suit period and traditional bathrooms. The design is the draw; the 1.6 gpf flush and uncertain availability are the drawbacks.
This review is based on Kohler’s specification sheet, product listings and warranty terms. We have not physically tested the K-3818; our methodology page explains how we research.
Status as of November 2026: Kohler still publishes a K-3818 spec sheet (revised October 2026), but Kohler’s online store listed it as out of stock, and Kohler’s Studio Kohler design site lists the K-3818 as discontinued. We consider its status unclear and likely being phased out. Kohler does offer current 1.28 gpf Memoirs Classic toilets, covered below.
Kohler Memoirs Classic K-3818 specifications
| Brand | Kohler |
|---|---|
| Model | Memoirs Classic K-3818 (K-4380 bowl + K-4641 tank) |
| Bowl shape compatibility | Elongated, Comfort Height (chair height) |
| Seat material | Vitreous china |
| Heated seat | No |
| Bidet features | No |
| Water heating | 1.6 gpf, AquaPiston gravity flush |
| Warm-air dryer | Unverified |
| Installation requirements | Standard 12 in. rough-in, three-bolt quick-connect; seat and supply line sold separately |
| Power requirements | Unverified |
| Warranty | Lifetime limited on vitreous china, 10-year mechanical, 1-year seat (residential) |
| Dimensions | Unverified |
Design: what makes it “Classic”
Kohler’s Memoirs collection comes in two styles. The Classic style uses rounded, layered detailing that Kohler compares to crown molding, while the Stately style uses straighter, more architectural lines. The K-3818 is the Classic version, built from the K-4380 elongated bowl and the K-4641 1.6 gpf tank.
Kohler says the K-3818 coordinates with other Memoirs Classic products, so you can match a pedestal sink or accessories. It has a left-hand polished chrome trip lever and an exposed trapway, meaning the drain curve is visible along the base, which suits the traditional look but takes more effort to wipe down than a skirted or concealed design.
If you prefer the cleaner-lined version of the same toilet, read our Memoirs Stately K-3819 review.
Flushing and water use
The K-3818 uses Kohler’s AquaPiston canister flush valve instead of a rubber flapper. Kohler says the canister optimizes the flow out of the tank using gravity, takes less force to operate than a 3-inch flapper, and has 90 percent less exposed seal material, which it says resists the wear and swelling that cause leaks. Kohler lists a 2-1/8 in. fully glazed trapway.
At 1.6 gpf, the K-3818 is at the federal limit and does not list EPA WaterSense certification on its spec sheet. EPA’s WaterSense label requires 1.28 gpf or less, which the agency says is 20 percent less water. Some local rebate programs only apply to WaterSense toilets, so check before you buy.
Height and comfort
The K-3818’s Comfort Height bowl is Kohler’s version of chair height. Kohler says it makes sitting down and standing up easier for most adults, and its toilet buying guide describes chair-height toilets as about 17 in. or more from the floor to the top of the seat.
Chair height suits most adults, especially taller people and those with stiff knees, but it may feel high for children or shorter adults. Our chair height vs standard height guide explains how to decide.
Exposed vs concealed trapway: does it matter?
The K-3818’s exposed trapway is the traditional design: the S-shaped channel that carries waste to the drain is molded into the side of the base, so you can see its curves. Many people like that look in a classic bathroom, and it leaves the floor bolts easy to reach during installation.
A concealed trapway, like the one on the Memoirs Classic K-6999, hides that channel behind smooth china walls. The flushing path is the same idea, but the outside is flatter and simpler to wipe clean. The trade-off is that installation can take a little more care, since the base hides the bolts.
Neither design is better at flushing by default; it is mostly a choice between traditional looks and easier cleaning. If you spend a lot of time scrubbing around the base of your current toilet, a concealed or skirted design is worth the switch.
Installation
Kohler lists a standard 12 in. rough-in and a three-bolt quick-connect installation. The seat and supply line are sold separately. The bowl uses standard 5-1/2 in. seat mounting holes, so most elongated seats will fit.
A two-piece toilet like this is a manageable DIY project for many homeowners, but call a licensed plumber if your flange is damaged, your floor is uneven or soft, or you’re unsure about the shutoff valve. For back-to-back installations, Kohler specifies a 45-degree double wye fitting.
Warranty
Kohler’s residential toilet warranty lists a lifetime limited warranty on vitreous china and ten years on mechanical components for most series, with a one-year warranty on seats. Memoirs is not among the series Kohler lists with a shorter five-year mechanical term. Read the full warranty document on Kohler’s site for exclusions.
Pros and cons
What we like
- Traditional Memoirs Classic styling that coordinates with matching sinks
- Comfort Height chair-height bowl
- AquaPiston canister instead of a flapper
- 2-1/8 in. fully glazed trapway
- Lifetime limited china and 10-year mechanical warranty per Kohler
Things to consider
- 1.6 gpf and not WaterSense certified
- Status unclear and likely being phased out
- Exposed trapway and detailed base take more cleaning
- Seat and supply line sold separately
Who it’s for
- Owners of traditional or period homes who want a toilet with molded detail rather than a plain modern profile.
- People replacing an existing Memoirs Classic who want a matching fixture.
- Adults who prefer chair-height seating.
It’s less ideal if you want the lowest water use or the easiest possible cleaning.
Current alternatives
Kohler publishes current spec sheets for two 1.28 gpf Memoirs Classic toilets that keep the same style and Comfort Height bowl:
| Model | Flush | Trapway | WaterSense |
|---|---|---|---|
| Memoirs Classic K-3818 | 1.6 gpf AquaPiston | Exposed, 2-1/8 in. | Not listed |
| Memoirs Classic K-3816 | 1.28 gpf AquaPiston | Exposed, 2-1/8 in. | Yes |
| Memoirs Classic K-6999 | 1.28 gpf AquaPiston | Concealed | Yes |
The K-6999’s concealed trapway hides the drain curve behind smooth sides, which Kohler pairs with low-profile Clean Caps bolt covers for easier cleaning. For a fully kitted alternative with a seat in the box, see our Kohler Transpose review.
What to check before you buy
- Model number. K-3818 (1.6 gpf), K-3816 (1.28 gpf) and K-6999 (1.28 gpf, concealed trapway) look similar online.
- Rough-in. Kohler lists 12 in.; measure from the finished wall to the bolt centers.
- Complete set. Confirm the listing includes both bowl and tank.
- Local rules. Check whether WaterSense is required for rebates in your area.
- Seat. Budget for an elongated seat; see our measuring guide.
Frequently asked questions
Does the Kohler Memoirs Classic K-3818 include a seat?
No. Kohler’s spec sheet says the seat and supply line are sold separately.
What is the difference between Memoirs Classic and Memoirs Stately?
The Classic style has rounded, molded detailing; the Stately style has straighter, more architectural lines. The 1.6 gpf K-3818 and K-3819 use the same K-4380 bowl but different tanks.
Is the K-3818 WaterSense certified?
No. It uses 1.6 gpf, and its spec sheet does not list WaterSense. The 1.28 gpf Memoirs Classic K-3816 and K-6999 do.
Next steps
Browse more models in our toilet reviews.
