Sump Pump Installation Cost Calculator
Sump Pump Installation costs $490 to $750 for a typical 1 pumps job in 2026, against a national benchmark of $600. Labor runs 2 crew hours at $42.44 an hour. Enter a ZIP code to apply that area's measured wages for this work and its regional price level.
What makes up the price
Cost by size
National averages, before any local adjustment. Computed from the same model as the calculator above, so the two always agree.
| How many pumps | Pumps | Typical | Range |
|---|---|---|---|
| 1 pumps | 1 | $600 | $490 to $750 |
| 2 pumps | 2 | $1,050 | $875 to $1,300 |
Three jobs that share a name
| One pump | |
|---|---|
| Replace the pump in an existing pit | $600 |
| Replace it and add a battery backup | $1,150 |
| Cut a new pit where there was none | $1,925 |
| New pit, plus a new discharge line | $2,400 |
| New pit in a crawl space | $2,325 |
If you do not know which of those you are being quoted, the quote is unreadable. The distinction is simple: does a pit already exist? If it does, this is a two-hour job and the pit will outlive several more pumps. If it does not, somebody is breaking out concrete, digging a hole by hand, bedding a liner in gravel, patching the slab and routing a discharge through the foundation wall — most of a day.
The discharge is where sump pumps fail
Not the pump. The pipe.
Three failures, all of them in the discharge line, and all of them avoidable:
1. It returns the water to the foundation. A discharge that ends two feet from the wall puts the water straight back into the soil that feeds the drain tile that feeds the pit. The pump then runs continuously, pumping the same water in a circle until it wears out. The line needs to end at least ten feet from the foundation and somewhere the water will run away rather than soak back down.
2. It freezes. A line that holds water, or that ends in a buried pipe that fills with ice, becomes a closed pipe. The pump then runs against it, overheats and burns out — in February, which is the worst possible time. Discharge lines in cold climates need to be pitched to drain completely and to have a freeze-relief fitting outside so that if the buried section blocks, the water has somewhere to go.
3. It goes into the sanitary sewer. Illegal in most jurisdictions, because it overwhelms treatment plants in storms, and routinely discovered at the point of sale. If you have just bought a house, this is worth looking at.
Two more: never into a window well, and never into a neighbor's yard, which is both unneighborly and in many places actionable.
The battery backup is the best money on this page
For $550 on top of a replacement, it is the single most sensible add-on in this part of the house, for one reason:
The power goes out in the storm that causes the flooding.
A primary pump with no backup is protection against a failed washing machine hose and a high water table. It is no protection at all against the thunderstorm that takes the power out, which is the event most people buy a sump pump for.
The options:
- A DC battery backup, which is a second pump on its own float with a deep-cycle battery and a charger-controller. It will run for several hours of intermittent pumping. The battery is a consumable — five to seven years — and a backup system with a dead battery is decoration. Note the date and replace it.
- A water-powered backup, which uses municipal water pressure to drive an ejector and needs no electricity at all. It never runs out, which is its great advantage, and it uses a gallon of city water for every two it pumps, which is its cost. Only possible on municipal water, and not permitted in some jurisdictions.
- A generator, which protects the whole house rather than just the pump, and is a different purchase.
If you choose a battery backup, ask for an alarm with it, or a Wi-Fi monitor for $50 to $150. A backup that quietly failed two years ago is the commonest version of a flooded basement in a house that had a backup.
The float switch is what fails
Sump pumps rarely die of a failed motor. They die of a failed switch, and that is worth knowing because it changes what to buy:
- A vertical float switch rides up and down a rod. It is more reliable in a narrow pit and cannot get hung up on the pit wall.
- A tethered float switch swings on a cord. It needs a wide pit, and in a narrow one it catches on the liner or the pipe — which is the classic failure where a pump sits dead with the water rising around it.
- Pressure and electronic switches avoid moving parts entirely and are good, with the caveat that electronics in a wet pit are electronics in a wet pit.
Two related points. A pit that is too small makes the pump short-cycle — on, off, on, off — and that is what wears out switches and motors. A proper pit is 18 inches across and 22 to 24 inches deep. And the little weep hole drilled in the discharge above the check valve is not a mistake: it stops the pump air-locking. If a pump runs but moves nothing, that is usually the first thing to look at.
Test it, quarterly
Thirty seconds, and it is the difference between finding out now and finding out at 2am:
- Pour a bucket of water into the pit until the float rises.
- Watch it start, pump out and stop cleanly.
- Go outside and confirm water is coming out of the discharge where you expect it.
- On a backup system, unplug the primary and repeat.
Step three is the one people skip and the one that catches a blocked or disconnected line.
It is the last line of defense, not the first
A sump pump deals with water that has already reached the foundation. Everything that stops it getting there is cheaper and more permanent:
- Downspouts discharging at least six feet from the wall, which is the single biggest cause of wet basements and the cheapest to fix.
- Gutters that are not blocked, since a blocked gutter sheets water down the wall.
- Grade sloping away from the house — six inches of fall in the first ten feet.
- Window wells that drain and are covered.
If the pump runs constantly in dry weather, something else is going on — a high water table, a spring, a broken water line or a failing drain tile — and that is a diagnosis rather than a bigger pump.
1/3 or 1/2 horsepower, cast iron or plastic
1/3 horsepower is enough for most houses. It will move 2,000 to 2,500 gallons an hour at a typical lift, which is far more than a residential drain tile delivers. A 1/2 HP pump is for a deep basement with a long vertical lift or a genuinely wet site, and in a normal house it mostly short-cycles harder.
Cast iron over plastic, and it is not snobbery: the cast iron housing sheds motor heat into the water around it, which is why cheap plastic-bodied pumps run hotter and fail sooner. A cast iron 1/3 HP pump with a vertical float is the specification most plumbers fit, and it is what the figures here assume.
What you are paying for
Replacing a pump in an existing pit, at $600:
| Submersible pump, check valve and fittings | $250 |
| Labor, about 2 hours | around $119 |
| The call-out | $75 |
| Overhead and margin | the balance |
A new pit instead is $1,925, of which $683 is labor — eleven and a half hours, because breaking out concrete and digging a hole by hand is most of a day, and the spoil has to leave the building in buckets.
Questions worth asking
- Is there an existing pit, or does one have to be cut?
- Where does the discharge line actually end?
- Is it pitched to drain, and is there a freeze-relief fitting?
- Does it discharge into the sanitary sewer?
- Vertical float or tethered?
- Cast iron or plastic, and what horsepower?
- Is a battery backup worth it here, and will it have an alarm?
- Is the pit the right size, or is the pump short-cycling?
- Is there a lid, and is radon a consideration in this area?
- Why is the pump running in dry weather?
Common questions
How much does sump pump installation cost?
About $600 to replace a pump in an existing pit, $1,150 to replace it and add a battery backup, and $1,925 to cut a new pit into a concrete floor where there was none. A new pit with a new discharge line is $2,400, and a new pit in a crawl space $2,325. The question that decides which of those you are buying is simply whether a pit already exists.
Why is a new sump pit so much more expensive than a replacement?
Because it is a different job. A swap in an existing pit is two hours — the pit outlives several pumps. Cutting a new one means breaking out concrete, digging the hole by hand, bedding a liner in gravel, patching the slab and routing a discharge through the foundation wall, which is eleven and a half hours of labor and several buckets of spoil carried out of the building. $600 against $1,925.
Where should a sump pump discharge?
At least ten feet from the foundation, onto ground that slopes away so the water runs off rather than soaking back down to the drain tile that feeds the pit. A discharge ending two feet from the wall makes the pump pump the same water in a circle until it wears out. Never into a window well, never into a neighbor's yard, and not into the sanitary sewer, which is illegal in most jurisdictions and routinely discovered at the point of sale.
Can a sump pump discharge line freeze?
Yes, and it is one of the three classic failures. A line that holds water, or a buried section that fills with ice, becomes a closed pipe — and the pump then runs against it, overheats and burns out in February. The protections are pitching the line so it drains completely and fitting a freeze-relief outside, so that if the buried part blocks, the water has somewhere else to go rather than nowhere.
Is a battery backup sump pump worth it?
It is the best money on this page, for one reason: the power goes out in the storm that causes the flooding. A primary pump alone protects against a failed washing machine hose and a high water table, and not at all against the event most people buy a sump pump for. It costs about $550 on top of a replacement. Ask for an alarm or a Wi-Fi monitor with it — a backup that quietly failed two years ago is the commonest version of a flooded basement in a house that had a backup.
How long does a sump pump battery backup last?
The battery is a consumable: five to seven years, and a backup system with a dead battery is decoration. Write the installation date on it and replace it on schedule rather than on failure. In a power cut a charged deep-cycle battery will run several hours of intermittent pumping, which covers most outages but not a multi-day one — that is where a generator or a water-powered backup comes in.
What is a water-powered backup sump pump?
An ejector driven by municipal water pressure, with no electricity involved at all, so it cannot run out the way a battery can. That is its great advantage. The cost is that it uses roughly a gallon of city water for every two gallons it pumps, it only works on municipal supply with decent pressure, and some jurisdictions do not permit them. For a house that loses power for days rather than hours, it is the more reliable choice.
Why does my sump pump run but not pump water?
Usually an air lock. There should be a small weep hole drilled in the discharge pipe between the pump and the check valve — it looks like a mistake and it is not; it lets trapped air escape so the impeller can prime. If that hole is missing or blocked, the pump spins without moving water. The other possibilities are a blocked or frozen discharge line and a check valve fitted the wrong way round.
What usually fails on a sump pump?
The float switch, not the motor. A tethered float swinging on a cord can catch on the pit liner or the pipe in a narrow pit, which is the classic failure where a pump sits dead while the water rises. A vertical float riding on a rod is more reliable in a narrow pit. A pit that is too small also kills pumps by making them short-cycle — on, off, on, off — and a proper pit is about 18 inches across and 22 to 24 inches deep.
How often should I test my sump pump?
Quarterly, and it takes thirty seconds. Pour a bucket of water into the pit until the float rises, watch it start, pump out and stop cleanly — then go outside and confirm water is actually coming out of the discharge where you expect it. That last step is the one people skip and the one that catches a blocked or disconnected line. On a backup system, unplug the primary and repeat.
What size sump pump do I need?
One third horsepower suits most houses: it moves 2,000 to 2,500 gallons an hour at a typical lift, which is far more than a residential drain tile delivers. Half a horsepower is for a deep basement with a long vertical lift or a genuinely wet site; in a normal house it mostly short-cycles harder. Choose cast iron over plastic — the iron housing sheds motor heat into the water, which is why cheap plastic-bodied pumps run hotter and fail sooner.
Why does my sump pump run all the time?
If it runs in dry weather, something specific is going on and a bigger pump is not the answer. The usual causes are a discharge line returning water to the foundation, a downspout discharging at the wall, a high water table or a spring, a broken water service line, or a failing drain tile. Check the discharge first, since it is free: if the water is coming out two feet from the wall, the pump is pumping the same water round in a circle.
Where these numbers come from
Nothing here is copied from a contractor directory. Labor is priced from what the trades are actually paid, materials from published producer prices, and both are adjusted to your area using federal cost-of-living data.
- Plumbing, heating and air-conditioning contractors, United States: $42.44/hour, August 2026 (BLS CES CES2023822003)
- Submersible pump, check valve and fittings: $250.00 per pump (price recorded October 2026, not index-adjusted)