Head-to-head · Best Garbage Disposals

InSinkErator Badger 5 1/2 HP vs InSinkErator Evolution Septic Assist 3/4 HP

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

InSinkErator Evolution Septic Assist 3/4 HP comes out ahead by a clear margin (4.0 vs 4.4). The gap is mostly about Homes on septic systems where chronic sludge buildup is a real concern and the buyer wants to use a disposer without compromising tank health. — read the strengths below before deciding.

Ranked #3 in Best Garbage Disposals

InSinkErator Badger 5 1/2 HP

4.0

$119

The Badger 5 is the most installed garbage disposer in North America and has been the default 1/2 HP swap-out unit for two decades. Reviewers (shouldit.com 5.3/10, This Old House 4.6/5) agree it is reliable, easy to install, and noisy. Buy it for small kitchens, apartments, and rentals; skip it for daily heavy cooking or noise-sensitive layouts.

Strengths

— Most widely installed 1/2 HP disposer in North America, with parts and service technicians available anywhere
— Compact 11-1/2 inch height fits the tightest under-sink cabinets
— Lift & Latch 3-bolt mount means most homeowners install it themselves in under an hour, especially as a swap-out for an older Badger

Watch-outs

— Single-stage grinder; struggles on fibrous waste, fish bones, and raw chicken in bench tests
— No SoundSeal insulation, so noticeably louder than any Evolution-series unit
— Only a 5-year warranty (half the warranty of mid-range Waste King units at similar street price)

$119 · Check Price on Amazon Full review →

Higher ratedRanked #5 in Best Garbage Disposals

InSinkErator Evolution Septic Assist 3/4 HP

4.4

$269

Septic Assist is the disposer to buy if your home is on a septic tank rather than a city sewer connection. It pairs an Evolution-series 3/4 HP MultiGrind chamber with InSinkErator's Bio-Charge injector, which doses enzyme-producing microorganisms into every cycle to keep septic-tank sludge from accumulating. Plan on cartridge refills as an ongoing cost.

Strengths

— Bio-Charge cartridge automatically injects 300 million enzyme-producing microorganisms per cycle to break down food waste and reduce septic-tank sludge buildup
— 3/4 HP Dura-Drive induction motor with 2-stage MultiGrind chamber matches the Evolution Compact's grinding performance
— Full SoundSeal Technology insulation and anti-vibration mount keep operation conversational

Watch-outs

— Bio-Charge cartridge needs replacing every 3-4 months at typical use (~$8 per cartridge, recurring cost)
— Some owners report the cartridge bottle dislodging during operation and splashing inside the cabinet
— Premium price for a 3/4 HP unit driven by the bio-charge mechanism rather than raw grinding power

$269 · Check Price on Amazon Full review →

How they stack up

InSinkErator Badger 5 1/2 HP

Roughly half the motor of the Evolution Compact 3/4 HP and a third of the Excel 1 HP, with single-stage grinding instead of MultiGrind. Lacks the bio-charge mechanism of the Septic Assist and the safety mechanism of the Cover Control Plus. The Badger's only structural advantage against any of those is its shorter cabinet footprint and roughly half their sticker price.

InSinkErator Evolution Septic Assist 3/4 HP

Shares the 3/4 HP MultiGrind chamber with the Evolution Compact but adds the Bio-Charge cartridge injection and is roughly $50 more. Comparable in price to the Cover Control Plus batch-feed, just with a different specialty (septic compatibility instead of safety). Less raw grinding power than the Excel 1 HP, but the Excel does not solve the septic compatibility problem.

Specs side-by-side

Spec	InSinkErator Badger 5 1/2 HP	InSinkErator Evolution Septic Assist 3/4 HP
Motor	1/2 HP Dura-Drive induction	3/4 HP Dura-Drive induction
Grind Stages	1 (single-stage)	2 (MultiGrind)
Feed Type	Continuous	Continuous
Chamber Capacity	26 oz galvanized	40 oz stainless steel
Mounting	3-Bolt Quick Lock with Lift & Latch	3-Bolt Lift & Latch
Overall Height	11-1/2 in	—
Weight	13 lb 10 oz	25.5 lb
Warranty	5-year We Come To You in-home	8-year We Come To You in-home
Sound Insulation	—	SoundSeal Technology
Septic Compatibility	—	Bio-Charge enzyme injection per cycle

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