Garbage disposal installation cost
Installing a garbage disposal costs $150 to $600 including the unit, typically $300. It goes up when there is no switch or socket under the sink, because then it is an electrician's job too.
National average
$300
per each
Installing a garbage disposal costs $150 to $600 including the unit, typically around $300. Labour alone is $100 to $250. It goes up when there is no switch, no socket under the sink, or the drain plumbing has to be rebuilt to meet it.
What it costs
| Job | Typical cost |
|---|---|
| Labour only, replacing an existing unit | $100 to $250 |
| 1/3 to 1/2 hp unit, installed | $150 to $400 |
| 3/4 to 1 hp unit, installed | $250 to $600 |
| Batch feed unit, installed | $350 to $800 |
| Adding a socket under the sink | $150 to $450 |
| Adding a wall switch | $150 to $400 |
| Air switch fitted in the countertop | $80 to $250 |
| New drain plumbing to suit the unit | $150 to $400 |
| Adding a dishwasher connection | $50 to $150 |
| Removal and disposal of the old unit | $25 to $75 |
The two electrical rows are the surprise. A first-time installation in a kitchen with no power under the sink is an electrician's job as well as a plumber's.
Sizing it
1/3 hp is the builder-grade unit in most new houses. It handles soft waste and jams on anything else. Skip it.
1/2 hp suits one or two people who scrape plates properly.
3/4 hp is the sensible default for a family kitchen. It clears bones and fibrous waste that stall a smaller motor, and it runs quieter because it is working less hard.
1 hp is worth it for a large household or a house with a long horizontal drain run where a stall means a blockage.
Sound insulation is the other axis. The cheap units are genuinely loud in an open plan kitchen, and the insulated models are worth the difference if the kitchen is part of a living space.
Continuous feed switches on at the wall and runs while you feed it. Batch feed only runs with the stopper in place, which makes it much safer around children and slower to use.
Septic systems
If you are on a septic tank, think twice. A disposal roughly doubles the solids going into the tank, which means pumping more often and a shorter drain field life. Some jurisdictions restrict them on septic outright.
Units sold as septic-safe inject enzymes; the useful part is the finer grind rather than the enzymes. If you have septic and want one, size the pumping schedule for it and check local rules first.
What actually kills them
Not bones. The three real ones:
Grease, which does not grind. It coats the chamber, then cools in the drain line downstream and catches everything that follows.
Fibrous waste in quantity: celery, artichoke, corn husks, onion skins. The strands wrap the impellers.
Starch in bulk: potato peel and rice turn into paste that sets in the trap.
Run cold water while grinding and for twenty seconds after. Cold keeps grease solid so it goes down in pieces rather than coating everything on the way.
Frequently asked questions
It hums but does not turn.
Jammed. Switch it off at the wall, put the hex key that came with it into the socket underneath, and work it back and forth. Then press the red reset button on the base. Never put your hand in the chamber, even with the power off.
It does nothing at all.
Press the reset button first, then check the breaker. If both are fine and it is more than eight years old, the motor has usually gone and a replacement is cheaper than a repair.
How long do they last?
Eight to fifteen years. The bearings and the motor go; the grinding components rarely wear out on domestic use.
Do I need a plumber or an electrician?
A plumber, if you are replacing an existing unit and the power is already there. Both, if it is a first installation with no socket or switch under the sink.
Does it damage the pipes?
No, but it changes what goes into them. A disposal feeding an old, sagging, or partly blocked drain line makes the blockage arrive sooner. If your kitchen drain already runs slow, fix that first.
Read next
Drain cleaning cost$100 to $800per eachClearing a blocked drain costs $100 to $800, averaging around $240. A single slow fixture is at the bottom of that; a main line backing up into several fixtures is at the top.
Septic tank pumping cost$300 to $700per eachPumping a septic tank costs $300 to $700, typically $450. It is the cheapest maintenance in the house measured against what it prevents: a failed drain field is $8,000 to $25,000.
Faucet installation cost$150 to $500per eachInstalling a faucet costs $150 to $500 including a mid-range fixture, typically $280. It is one of the few plumbing jobs where the cost is dominated by how awkward the space under the sink is.
Plumber cost by state$75 to $150per hourA plumber bills $85 an hour in Arkansas and $140 in Illinois. A 65% spread on the same hour of the same work, and it is almost entirely wages.
How long does plumbing last$4,500 to $12,000per projectCopper lasts 50 to 70 years, PEX 40 to 50, cast iron drain 50 to 100. Plumbing is the system that fails quietly for years and then all at once, and the material in your walls says roughly where you are.