Head-to-head · Best Bidet Toilet Seat Attachments

Brondell SimpleSpa Thinline Essential (SS-150) vs TOTO Washlet S5 (SW3446)

Which is the better buy? Side-by-side on rating, price, strengths, and watch-outs — with the published ratings we averaged to get there.

The short answer

TOTO Washlet S5 (SW3446) comes out ahead by a clear margin (4.3 vs 4.7). The gap is mostly about buyers who want the full electric-seat experience with a heated seat, dryer, and endless warm water and have a nearby outlet — read the strengths below before deciding.

Ranked #5 in Best Bidet Toilet Seat Attachments

Brondell SimpleSpa Thinline Essential (SS-150)

4.3

$35.99as of Jun 7

The Brondell SimpleSpa Thinline Essential is the budget entry point: an ultra-slim 0.2-inch attachment that tucks under your existing seat without adding a noticeable gap, built with surprisingly good brass-and-ceramic internals and a braided metal hose. It is single-nozzle, cold-water only, and basic by design, but for around $50 it nails the fundamentals - adjustable pressure, a self-cleaning nozzle, and a tool-free install - which makes it the easiest low-cost way to try a bidet.

Strengths

— Ultra-slim 0.2-inch profile fits under the existing seat without creating a gap
— Brass and ceramic internal components with a braided metal hose and all-metal T-valve
— Fully adjustable water pressure via an easy-turn side knob

Watch-outs

— Single nozzle and cold water only - no feminine wash or warmth
— Side-arm knob is basic next to dual-control attachments
— No self-lift hinge for bowl cleaning like the Luxe

$35.99 · Check Price on Amazon Full review →

Higher ratedRanked #1 in Best Bidet Toilet Seat Attachments

TOTO Washlet S5 (SW3446)

4.7

$682as of Jun 7

The TOTO Washlet S5 is the premium pick - a full electric bidet seat that replaces your toilet seat and adds a heated seat, instantaneous endless warm water, a warm-air dryer, automatic deodorizer, and self-cleaning wand tech (EWATER+ and PREMIST). Wirecutter named it the best bidet seat. It costs roughly ten times an attachment and needs a power outlet, and a few owners report leaking over time, but for the full luxury experience nothing here is close.

Strengths

— Instantaneous water heater delivers endless warm water at 95-104F
— Heated seat (82-97F) with warm-air dryer (three temps) and automatic deodorizer
— Front, rear, and soft-rear washes with oscillating and pulsating options

Watch-outs

— Far more expensive than any non-electric attachment, often $700+
— Requires a nearby GFCI power outlet - electrician may be needed
— Some owners report occasional water leaking over time

$682 · Check Price on Amazon Full review →

How they stack up

Brondell SimpleSpa Thinline Essential (SS-150)

The budget pick - it is the simplest and cheapest here, undercutting the Luxe Bidet Neo 320 Plus and both Tushy models while skipping their dual nozzles, warm water, and self-lift hinges; it is the polar opposite of the luxury electric TOTO Washlet S5, trading every feature for a rock-bottom price and an ultra-thin fit.

TOTO Washlet S5 (SW3446)

The luxury electric seat in this lineup - it adds a heated seat, warm-air dryer, deodorizer, and instantaneous endless warm water that no non-electric attachment can match, but it costs roughly ten times the Luxe Bidet Neo 320 Plus or Tushy Classic 3.0 and needs a power outlet; the Tushy Spa 3.0 approximates its warm water without electricity, and the Brondell SimpleSpa Thinline is its budget opposite.

Specs side-by-side

Spec	Brondell SimpleSpa Thinline Essential (SS-150)	TOTO Washlet S5 (SW3446)
Type	Non-electric clip-on attachment	Electric bidet seat (washlet)
Nozzles	Single, self-cleaning retractable	—
Water Temperature	Cold only	—
Pressure Control	Adjustable side-arm knob	—
Profile	0.2 in thick (no-gap fit)	—
Materials	Brass + ceramic internals, braided metal hose	—
Power	None - water pressure driven	—
Warranty	1 year limited	—
Water Heating	—	Instantaneous, 95-104F (endless)
Heated Seat	—	Adjustable 82-97F
Dryer	—	Warm air, 3 temperatures (95-140F)
Wash Modes	—	Front, rear, soft rear; oscillating + pulsating
Self-Cleaning	—	EWATER+ wand + PREMIST bowl
Remote	—	Wireless, memory for 4 users
Fit	—	Elongated

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