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TOTO Toilet Seats

Selecting and replacing seats for TOTO toilets — from the standard SoftClose to the full Washlet electronic seat. Covers bowl-shape fit, mounting hardware, and how to choose between TOTO-branded and universal-fit alternatives.

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Updated May 2026 · TOTO Toilets

TOTO seats split into two universes: the standard mechanical seat (soft-close or non-soft-close, no electronics), and the Washlet electronic seat (heated, bidet wash, dryer — essentially a smart-toilet seat that replaces a normal seat). The two categories use the same mounting bolts on the same bowls — meaning you can upgrade from a standard TOTO seat to a Washlet at any time without changing the toilet bowl.

The first decision: standard or Washlet?

A TOTO bowl with a standard SoftClose seat looks and functions like any other US toilet — just better-engineered, with a hinge mechanism that closes slowly without slamming. Cost: $35–$120.

A TOTO bowl with a Washlet seat becomes effectively a smart-toilet experience — heated seat, integrated bidet wash, warm-air dryer, sometimes auto-flush. Cost: $400–$1,800 for the seat itself, plus a GFCI outlet within 3 feet (which most US bathrooms lack). See our TOTO bidet integration page for the full upgrade decision.

Standard TOTO seats (mechanical)

  • SS113 (elongated soft-close) ($45–$75) — TOTO's volume soft-close seat. Fits Drake, Drake II, Vespin II, UltraMax II, Aquia IV. Plastic, slim profile, two-button hinge release for easy cleaning. The most-recommended TOTO seat replacement.
  • SS114 (round soft-close) ($45–$70) — round-front variant of SS113. Fits Drake Round and other round TOTOs.
  • SS124 (commercial-grade elongated soft-close) ($90–$140) — heavy-duty version with reinforced hinges; spec'd for hotels and Airbnbs.
  • SS204 (designer elongated) ($95–$140) — Curved profile with extended seat depth; pairs well with Vespin II and Carlyle II.
  • SS214 (heated, non-bidet seat) ($240–$320) — heated seat only (no wash). Sub-Washlet entry tier for cold-climate bathrooms.

Universal seats that fit TOTO bowls

TOTO uses the standard US 5.5-inch bolt-spread mounting holes on virtually all current residential bowls. Universal-brand seats fit without issue:

  • Bemis 1500EC (elongated soft-close) — $35. The universal soft-close that fits TOTO, Kohler, and American Standard. Color matches "Cotton White" reasonably well.
  • Mayfair Adjustable Slow-Close — $30. Adjustable mount, fits any standard bolt-spread.
  • Brondell Swash 1400 (electronic bidet seat) — $400–$580. Universal-fit electronic bidet seat that fits TOTO Drake II, Vespin II, Aquia IV. The non-Washlet alternative for adding bidet functions to a TOTO bowl.
  • Bio Bidet BB-2000 Bliss — $480. Another universal electronic bidet seat that fits TOTO Drake-series bowls.

How to identify which TOTO seat you need

  1. Determine bowl shape. Measure from bolt holes to front of bowl: 16.5" round, 18.5" elongated. Some TOTO compact-elongated models (Aquia IV) measure 17.5" — universal elongated seats fit but may have minor overhang.
  2. Identify the bowl model. The model number is printed under the tank lid (e.g., "CST454CEFG" for Drake II). Look up the matching seat SKU on TOTO USA's customer service site.
  3. Decide standard vs Washlet. Standard seat = $35–$140. Washlet seat = $400–$1,800. The bowl accepts both; this is your choice.
  4. Color match. TOTO seats come in Cotton White (#01), Sedona Beige (#12), Bone (#03), and Ebony (#51). Match to your bowl color code (printed near the model number).

The TOTO SoftClose mechanism — what's actually engineered

TOTO's SoftClose hinge uses a sealed cylinder containing silicone oil and an internal piston. When you press the lid down, the piston encounters resistance, decelerating the lid to a soft-close completion. The mechanism is rated for ~25,000 cycles before the oil seal degrades and the soft-close becomes erratic — about 8–12 years of typical household use. When it fails, the seat replacement is usually the only fix; hinge mechanisms aren't sold separately for the SoftClose line.

The seat-replacement procedure (10 minutes)

  1. Lift the bolt caps at the back of the bowl (small flathead screwdriver to pop them open).
  2. From inside the tank or below the rim, hold the bolt heads while unscrewing the plastic nuts underneath.
  3. Lift the old seat off the bowl.
  4. Clean the mounting area — under bolt caps accumulates the worst grime.
  5. Position new seat. TOTO seats include color-matched bolts and grippers; align with mounting holes.
  6. Tighten plastic nuts hand-tight only (never use pliers; you'll crack the porcelain).
  7. Snap bolt caps closed. Test by lifting/lowering the lid.

Bidet-seat compatibility note

If you're upgrading from a standard SoftClose seat to a Washlet or other electronic bidet seat, the install is the same procedure plus a water-line tee connection (T-adapter splits the toilet's water supply between the tank fill and the bidet wash) and a GFCI outlet within 3 feet. See our TOTO bidet integration page for the full procedure.