Garbage Disposal Installation Cost Calculator

Most installations run $150 to $500 including the unit and labor, with typical jobs around $250 to $400. The disposal itself is $80–$400+ (a basic 1/3 HP at the low end, a premium 1 HP at the top), and install labor adds $80–$250. A straight replacement using existing wiring and plumbing is cheapest; a brand-new install that needs a new outlet, switch, and drain work is the most. Power level, install type, switch, and drain work are the four levers in the calculator.

Match power to your household. A 1/3 HP unit suits very light use but is underpowered and jams easily, so most people skip it. A 1/2 HP is the popular default for average households and everyday food waste. A 3/4 HP is the sweet-spot upgrade for larger households or frequent cooking — it grinds tougher, fibrous waste, jams less, and usually runs quieter. A 1 HP handles heavy use and is the quietest and most durable. For most homes, 1/2 to 3/4 HP is the right call.

A continuous-feed disposal runs while you feed waste in and is switched on at the wall or an air switch — it's the common, convenient, lower-cost type. A batch-feed disposal only runs when you drop in a special stopper lid and turn it, so it can't run with the opening exposed — safer around kids and needs no separate switch, but it costs more and grinds in batches. Continuous-feed is the default for most homes; batch-feed is the safety-first choice. The calculator's premium tier covers batch-feed and quiet models.

A replacement reuses everything that's already there — the sink flange and mounting, the drain connection, and the electrical (an outlet and switch) — so the plumber just unhooks the old unit and hangs the new one. A new install where none existed has to add those systems: a dedicated outlet under the sink, a wall or air switch (often an electrician and possibly a new circuit), and drain/trap modifications. That extra electrical and plumbing is why a no-hookups install runs about 50% more than a straight swap.

It needs a power connection — usually a grounded outlet under the sink (or a hardwired feed) — controlled by a switch, either a standard wall switch or a countertop air switch. A dedicated circuit is ideal and sometimes required by local code, though disposals are often on a circuit shared with the dishwasher. On a replacement, all of this already exists. On a new install, it has to be added, which is the electrical portion of the higher cost. Always check local code on whether a dedicated circuit is required.

An air switch is a small button mounted on the countertop or sink that turns the disposal on and off through a puff of air, with no electricity at the button itself. It's handy when there's no convenient wall switch, when you want a cleaner look, or for safety since it can sit right at the sink. It's a modest per-unit add-on in the calculator. If you already have a working wall switch and like it, you don't need one — it's a convenience upgrade, not a requirement.

Yes — most disposals have a dishwasher inlet so the dishwasher's drain hose ties into the disposal, letting food particles get ground and flushed. If you're adding that connection (or it wasn't there before), it's a small drain-work add-on because the installer has to knock out the disposal's inlet plug and route and clamp the hose. On a like-for-like replacement where the dishwasher was already connected, it's usually just reconnected as part of the standard job.

Replacing an existing disposal is a popular DIY job — with the mounting, drain, and outlet already in place, a handy person can swap it in 1–2 hours. The keys are shutting off power at the breaker, making tight leak-free plumbing connections, and testing before you trust it. A new install is a different story: adding an outlet, a switch or new circuit, and drain plumbing is best left to a plumber and/or electrician. When in doubt, hire out — an under-sink leak or bad wiring costs far more than the install.

For a simple like-for-like replacement, usually not. But a new installation that adds electrical (a new outlet, switch, or circuit) or modifies drain plumbing often requires a permit and inspection, and some jurisdictions require one for any disposal work. Permits are inexpensive relative to the job and protect you at resale and with insurance. The calculator includes a permit add-on so you can budget for it; your installer will know what your local building department requires.

A replacement is quick — typically 1 to 2 hours, including removing the old unit, mounting the new one, connecting the drain and dishwasher line, wiring it, and leak-testing. A new install that needs an outlet, a switch or circuit, and drain plumbing runs longer, often 2–4+ hours and sometimes two trades. Corroded old fittings, a stuck unit, or tight cabinet space can add time. Most jobs finish in a single visit.