The best 1 HP sump pumps

One horsepower buys lift, not reliability. It is the right answer for a deep discharge or a long run to daylight, and the wrong answer for a standard basement.

Buy a 1 HP sump pump for lift, not for peace of mind. Of the three we could verify as currently sold, the Flotec FPZT7550 is the one we would fit: it publishes the highest flow at ten feet of lift and it is the only one that keeps the standard 1-1/2 inch discharge, so it goes into existing plumbing unchanged. The Basement Watchdog BWSS100 is the better-built pump and the only one with a redundant switch. The Superior Pump 92151 is the budget route and publishes the most complete flow curve. But the most useful recommendation on this page is the fourth pick: for most houses, a cast-iron 3/4 HP pump and a properly sized pit beat a 1 HP pump in a pit that is too small.

The residential 1 HP class is much thinner than the search volume suggests. Below 1 HP there are dozens of pumps from Zoeller, Liberty, Wayne and Superior. At 1 HP, consumer-channel options narrow to a handful, and most of what a search surfaces at that rating is either a sewage or effluent pump built for a different job, a dewatering pump for contractors, or a marketplace listing whose horsepower claim does not match the model number. That is worth knowing before you shop, and it is why this page names what it checked.

Quick picks

#	Product	Best for	Score	Price
1	Flotec FPZT7550 (1 HP zinc body)The highest published flow at ten feet of lift of any 1 HP pump we could verify, and the only one that keeps the standard 1-1/2 inch discharge.	The 1 HP pump that fits the plumbing you already have	8.8★★★★	Check price on Amazon → #ad we earn a commission · Amazon shows the current price
2	Basement Watchdog BWSS100 (1 HP stainless)Stainless housing on a cast-iron base, a caged dual float and a separate controller — the most monitored 1 HP pump on the page, with the least settled specification sheet.	A 1 HP pump that comes with its own switch controller	8.3★★★★	Check price on Amazon → #ad we earn a commission · Amazon shows the current price
3	Superior Pump 92151 (1 HP stainless and cast iron)The cheapest 1 HP pump we could verify as currently sold, and the only one that publishes a flow curve all the way out to twenty feet of lift.	The budget route into 1 HP	8.2★★★★	Check price on Amazon → #ad we earn a commission · Amazon shows the current price
4	Zoeller 1099 (3/4 HP dual-switch submersible)A 3/4 HP cast-iron pump with dual switching that covers almost every residential lift, at lower amps and lower cost than anything above it.	The pump most people searching for 1 HP should actually buy	8.8★★★★	Check price on Amazon → #ad we earn a commission · Amazon shows the current price
5	Jackel SF20 sump basin (18 x 22 in)An 18 by 22 inch, 20 gallon basin — because a high-flow pump in a small pit does not pump faster, it just starts more often.	The pit a 1 HP pump needs	8.8★★★★	Check price on Amazon → #ad we earn a commission · Amazon shows the current price

Scores are ours and editorial, not lab measurements — see how we pick. Tap a row for the full write-up.

Do you actually need 1 HP?

Horsepower in a sump pump does one thing: it moves water against height. The number that decides what you need is total dynamic head — the vertical lift from the pump's off point to the highest point in the discharge line, plus the friction of the pipe, elbows and check valve on the way. Four situations genuinely call for 1 HP:

• A deep basement with a high discharge. A pit floor twelve feet below grade, with the pipe exiting above the frost line and running up to a yard slope, can total eighteen to twenty-two feet of head. Most 1/3 and 1/2 HP pumps are at or past their shut-off head there.
• A long horizontal run. Discharge that travels eighty or a hundred feet to a legal outlet adds friction loss that behaves like extra lift. Sump pump discharge pipe size covers how much.
• A wet lot that outruns the pump in a storm. If a healthy 3/4 HP pump runs continuously and the pit still rises during heavy rain, you have a volume problem rather than a failure. That is the real case for more capacity.
• Two pumps sharing one discharge. When a primary and a backup, or two primaries, tie into a single line, the effective head each one sees rises.

If none of those describes your house, the honest answer is that 1 HP will not make your basement drier. It will empty the pit faster, start more often, draw more current and cost more. A pump that short-cycles wears out sooner than one that runs sensible cycles, so over-sizing can reduce reliability rather than add to it.

What changes when you fit 1 HP

Going up a class is not a drop-in swap. Four things change, and the first two cost money that is not in the pump's price.

1. The circuit. These pumps draw 6.3 to 7.9 A at 115 V. On a 15 A branch shared with a freezer, a dehumidifier and a light, a motor starting surge in a storm is how a breaker trips at the worst possible moment. A dedicated circuit is the correct install for a 1 HP pump, and it is usually the biggest single line in the bill.
2. The discharge size. Two of the three 1 HP pumps here have a 2" outlet. Fitting one to existing 1-1/2 in pipe means a reducer immediately above the pump, which throttles exactly the capacity you bought. Either repipe to 2 in or buy the 1-1/2 in pump.
3. The pit. Higher flow against the same small basin means shorter, more frequent cycles. If the pump empties the pit in four seconds, the basin is the limit, not the motor.
4. The check valve. More flow means a harder slam when the valve closes and a bigger column of water falling back if it does not seat. How a sump pump check valve works explains why this gets louder as capacity goes up, and why is my sump pump so loud covers the noise you may have just bought.

How we ranked this

Five criteria, applied in this order, with the ranking written before any buy link was added:

1. Is there a published flow figure at a stated lift? A headline figure at zero lift is marketing. A figure at ten, fifteen or twenty feet is a specification you can size against. One pump here publishes four points and one publishes none.
2. Does it fit the plumbing in a normal pit? A 1-1/2 in discharge is a swap. A 2 in discharge is a repipe or a reducer that gives back performance.
3. What is the switch, and is there a second one? The switch fails before the motor on almost every pump ever made. A caged dual float is worth real money at this capacity.
4. What is the pump made of? Cast iron and stainless sink heat into the water and survive a permanently wet pit; zinc and thermoplastic are lighter and cheaper.
5. What does it draw, and on what circuit? A pump that trips a breaker in a storm is not a pump.

The published specifications, side by side

#1The 1 HP pump that fits the plumbing you already have

Flotec FPZT7550 (1 HP zinc body)

The highest published flow at ten feet of lift of any 1 HP pump we could verify, and the only one that keeps the standard 1-1/2 inch discharge.

8.8/10★★★★★Our editorial score: 8.8 out of 10

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Specifications, as published by Flotec (Pentair)

Type	Submersible, cast zinc body
Horsepower	1 HP
Electrical	115 VAC, 60 Hz; 7.9 A per distributor listings
Discharge	1-1/2" NPT
Switch	Vertical float, on at 7-1/2", off at 3"
Maximum head	29 ft per distributor listings; Pentair publishes flow at 10 ft rather than a shut-off head
Cord	8 ft
Minimum basin	10 in diameter
Flow, by lift	6,660 GPH at 0 ft · 4,980 GPH at 10 ft
Warranty	Three years, limited

This is the pump we would fit if a genuine 1 HP need had been established, and the reason is boring: it is the only one of the three that does not force you to change the plumbing. Both other 1 HP pumps here discharge at 2 inches. A 1-1/2 inch pump drops straight onto the union, the check valve and the pipe already in your pit.

The flow number is the other argument. Pentair publishes 6,660 GPH at zero lift and 4,980 GPH at ten feet, and it is the second of those two that decides anything. Our 3/4 HP picks publish about 3,200 to 3,500 GPH at ten feet, so this is a real step up rather than a badge — and at fifteen or twenty feet of lift, which is where tall basements and long runs to daylight land, that gap widens.

Be honest about the body material, though. This is cast zinc. Zinc resists corrosion well and the motor is sealed, but in the pit-material hierarchy most installers carry in their heads — cast iron, then stainless, then engineered plastic — zinc is an unfamiliar entry rather than a premium one. If your pit is wet twelve months a year, the stainless and cast-iron options below are the more conservative buy even though they move less water.

Reality check on amps before you order. 7.9 A at 115 V on a 15 A circuit shared with a freezer and a dehumidifier is how breakers trip in a storm, which is the single worst moment for a pump to be offline. If you are stepping up to 1 HP, the honest install is a dedicated circuit — see sump pump tripping breaker for the diagnostic that comes first.

What it gets right

• 4,980 GPH published at ten feet of lift — the highest figure at a stated lift of any 1 HP pump we verified, and about 55% more than the 3/4 HP pumps on this site
• 1-1/2 in NPT discharge, so it drops into existing sump plumbing without repiping or a reducer at the check valve
• Pentair publishes the switch trip points (on at 7-1/2 in, off at 3 in), which is how you work out how much water sits in the pit between cycles
• Fits a 10 in minimum basin, the smallest requirement of the three 1 HP pumps here
• 7.9 A at 115 V per distributor listings — the figure matters, and it is published
• Three-year limited warranty, and Pentair's dealer network is deep enough that parts are not a gamble

Where it falls short

• Cast zinc body, not cast iron or stainless. Zinc is corrosion-resistant and it is what this model is, but it is not the material you would choose for a pit that stays wet year-round
• Pentair publishes flow at ten feet but no shut-off head; the 29 ft maximum head figure comes from distributor listings rather than from the manufacturer
• No solids-handling figure is published anywhere we could reach, which matters if your pit silts up
• 8 ft cord is the shortest here, so a pit far from an outlet becomes an electrician's job rather than a plug-in
• Sold through plumbing and industrial distribution more than consumer retail, so you are usually ordering it rather than collecting it

Specifications from Pentair Flotec FPZT7550 product page: 1 HP, zinc body, 6,660 GPH maximum, 4,980 GPH at 10 ft, 1-1/2 in NPT, vertical float on at 7-1/2 in / off at 3 in, 8 ft cord, 10 in minimum basin, three-year limited warranty, Distributor listing quoting 115 V, 7.9 A, 29 ft maximum head and 4,980 GPH, in stock (checked 2026-11-12).

#2A 1 HP pump that comes with its own switch controller

Basement Watchdog BWSS100 (1 HP stainless)

Stainless housing on a cast-iron base, a caged dual float and a separate controller — the most monitored 1 HP pump on the page, with the least settled specification sheet.

8.3/10★★★★★Our editorial score: 8.3 out of 10

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Specifications, as published by Basement Watchdog

Type	Submersible, stainless steel housing with a cast-iron base and impeller
Horsepower	1 HP
Motor	Permanent split capacitor, about 6.3 A at 115 V per retail listings
Discharge	2"
Switch	Caged dual float switch supplied with its own controller
Cord	10 ft
Weight	About 36 lb
Maximum head	Not settled: 26 ft on one distributor listing, 32 ft on another, and the manufacturer does not publish a figure we could reach
Flow, by lift	6,540 GPH at 0 ft · 4,400 GPH at 10 ft
Warranty	Three years, limited

Basement Watchdog's reputation is built on controllers and dual-float switching rather than on pump castings, and this is what that philosophy looks like applied to a primary pump. The switch is a caged dual float with its own controller, which is a meaningfully different design from the single vertical float on every other pump on this page.

That matters because of what actually kills sump pumps. Motors rarely fail first; switches do. A caged dual float gives the system a second chance to notice rising water, and on a 1 HP pump — which is usually fitted because the consequences of not pumping are expensive — a redundant switch is worth more than a few hundred gallons an hour. The materials back it up: stainless housing, cast-iron base, cast-iron impeller.

The frustration is the paperwork. We could not reach a manufacturer specification sheet for this model, and the distributor listings disagree with each other on maximum head by six feet. We have recorded both figures rather than picking the flattering one, but if your discharge rises more than about twenty feet, this is not the pump to buy on faith. The sister systems are covered in the Basement Watchdog Big Combo review.

What it gets right

• 4,400 GPH at ten feet of lift on the Lowe's listing, within a whisker of the highest figure here, from 6,540 GPH at zero
• Stainless steel housing with a cast-iron base and a cast-iron impeller — the material combination most installers would pick for a permanently wet pit
• Caged dual float switch supplied with its own controller, so a single stuck float does not take the pump out: this is the one real reliability feature in the 1 HP class
• Permanent split capacitor motor drawing about 6.3 A, the lowest draw of the three 1 HP pumps, which makes a shared circuit slightly less marginal
• 10 ft cord and a mainstream retail path — Home Depot, Lowe's and Ace all list it, so you can usually collect one the same day
• Three-year limited warranty

Where it falls short

• The maximum head figure is not settled: one distributor says 26 ft, another says 32 ft, and we found no manufacturer number. On a page about lift, that is the figure you most want and cannot get
• Two retailers quote 4,400 GPH at ten feet and two quote 4,440. The difference is trivial; the fact that nobody is quoting a manufacturer sheet is not
• 2" discharge, so fitting it to an existing 1-1/2 in line means a reducer, which gives back part of the flow you paid for
• 36 lb, the heaviest pump here, which matters when you are lifting it out of a pit at arm's length for the annual clean
• The controller is another box, another plug and another thing to mount — more capability and more to go wrong

Specifications from Home Depot listing for the BWSS100: 1 HP, cast iron and stainless steel, caged float switch and controller (checked 2026-11-12), Lowe's listing quoting 6,540 GPH at 0 ft and 4,400 GPH at 10 ft on a permanent split capacitor motor (checked 2026-11-12), Big Frog Supply listing for the BWSS100, which quotes 4,440 GPH at 10 ft rather than 4,400.

#3The budget route into 1 HP

Superior Pump 92151 (1 HP stainless and cast iron)

The cheapest 1 HP pump we could verify as currently sold, and the only one that publishes a flow curve all the way out to twenty feet of lift.

8.2/10★★★★★Our editorial score: 8.2 out of 10

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Specifications, as published by Superior Pump

Type	Submersible, stainless steel housing with a cast-iron base
Horsepower	1 HP, continuous duty, thermally protected split capacitor
Electrical	120 V, 7.5 A, 15 A minimum circuit
Discharge	2" NPT side discharge
Switch	Vertical float, on at 16", off at 8"
Impeller	Thermoplastic
Solids handling	1/2"
Maximum head	25 ft
Cord	10 ft
Flow, by lift	5,160 GPH at 0 ft · 4,500 GPH at 10 ft · 4,080 GPH at 15 ft · 3,660 GPH at 20 ft
Warranty	Three years

Superior Pump is a value brand and this is a value pump, but it earns its place here on disclosure. It is the only 1 HP pump on this page that publishes flow at four separate lifts, and lift is the entire reason anybody shops this class. When a manufacturer shows you 3,660 GPH at twenty feet, you can size against it. When a manufacturer shows you one headline number at zero lift, you are guessing.

The switch is the honest weak point. On at sixteen inches, off at eight, is a long throw: the pit fills a long way before the pump starts and empties a long way before it stops. In a deep 22 inch basin that is efficient, because each cycle moves a lot of water and the motor starts less often. In a shallow basin it is a pump that is either running or about to.

The other caution is a buying one rather than an engineering one. Model number 92151 appears on reseller listings describing a 1/3 HP cast-iron pump, which is a different product entirely. Buy from a retailer whose own listing says 1 HP, stainless steel and cast iron, with the vertical float switch — and if the box says otherwise, send it back.

What it gets right

• The budget pick on this page by a clear margin, and it is a real 1 HP pump rather than a relabeled 3/4
• The only 1 HP pump here with a published curve at four points: 5,160 GPH at zero, 4,500 at ten feet, 4,080 at fifteen and 3,660 at twenty. If you are buying for lift, buy from a curve
• Stainless steel housing over a cast-iron base, continuous-duty thermally protected split capacitor motor
• 1/2" solids handling is published, which neither other 1 HP pump here states
• 7.5 A on a stated 15 A minimum circuit — again, published rather than inferred
• Three-year warranty and wide retail distribution

Where it falls short

• 25 ft maximum head, the lowest of the three. Above about twenty feet of lift this is the wrong pump on this page
• Thermoplastic impeller behind a stainless housing. It is the cheapest part of the pump and it is in the water path
• Vertical float with a long throw: on at 16", off at 8". That is a lot of water cycling through the pit, and it needs a deep basin to work properly
• 2" NPT side discharge, so the same reducer problem as the Basement Watchdog, plus a side outlet that changes how the pipe leaves the pit
• Marketplace listings for model 92151 are a mess — we found resellers describing the same number as a 1/3 HP cast-iron pump. Buy from a listing that states 1 HP and stainless, and check the box

Specifications from Home Depot listing for the 92151: 1 HP submersible stainless steel and cast iron sump pump with vertical float switch (checked 2026-11-12), Zoro listing for the 92151 quoting 5,160 GPH at 0 ft, 4,080 GPH at 15 ft, 1/2" solids, stainless housing, vertical switch at 16 in on / 8 in off.

#4The pump most people searching for 1 HP should actually buy

Zoeller 1099 (3/4 HP dual-switch submersible)

A 3/4 HP cast-iron pump with dual switching that covers almost every residential lift, at lower amps and lower cost than anything above it.

8.8/10★★★★★Our editorial score: 8.8 out of 10

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Specifications, as published by Zoeller

Type	Submersible, cast iron, dual switch
Horsepower	3/4 HP
Switch	Vertical float
Line	Zoeller at Home consumer range, sold through Lowe's
Flow, by lift	4,800 GPH at 0 ft

Putting a 3/4 HP pump in a 1 HP roundup needs justifying, so here it is. Horsepower in a sump pump buys lift, and the lift in a normal house is eight to twelve feet from the pit to the point where the pipe leaves the wall. Every pump on this page clears that with room to spare. What a bigger motor does in that house is pull more amps, cost more money and empty the pit faster, which makes the pump start more often rather than less.

So the honest recommendation for most people who search for a 1 HP sump pump is a well-built 3/4 HP pump and a correctly sized pit. The 1099 is cast iron, dual-switched and backed by the best parts network in the category. The full write-up of the class is in the best 3/4 HP sump pumps, and the step below it is in the best 1/2 HP sump pumps.

The one place we will not defend Zoeller is disclosure. The consumer range gives a single flow figure at zero lift and no shut-off head at all, which is exactly the number that cannot be used for sizing. If you need to calculate rather than assume, the Superior above and the Flotec at the top of the page both publish figures you can work with.

What it gets right

• 3/4 HP covers the lift in the overwhelming majority of houses, which is the single most useful fact on this page
• Cast iron, dual switch, and Zoeller's service-part network — the brand plumbers reach for when the pump has to last
• Lower amp draw than any 1 HP pump, so it is far less likely to force a new circuit
• Costs less to buy and less to run, and runs shorter cycles in a correctly sized pit
• 4,800 GPH published at zero lift, which is more than the 1 HP Superior manages at zero
• Sold through consumer retail, so it is easy to get in a hurry

Where it falls short

• Zoeller's consumer range publishes no flow figure at a stated lift for this model and no maximum head, so you cannot size it properly from the manufacturer's own numbers — the worst disclosure on this page
• At genuinely high lift — a walk-out discharge twenty feet above the pit, or a long run with several elbows — it will be working harder than a 1 HP pump and will not match them
• No published solids handling
• If your reason for shopping 1 HP is that your current 3/4 HP pump cannot keep up, this is not the upgrade; it is the same class again

Specifications from Zoeller at Home sump pump range (1099-0001 listed, checked 2026-10-29), Zoeller 1099-0001 retail listing stating 3/4 HP, 80 GPM, cast iron, vertical float.

#5The pit a 1 HP pump needs

Jackel SF20 sump basin (18 x 22 in)

An 18 by 22 inch, 20 gallon basin — because a high-flow pump in a small pit does not pump faster, it just starts more often.

8.8/10★★★★★Our editorial score: 8.8 out of 10

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Specifications, as published by Jackel

Size	18 in diameter x 22 in deep
Capacity	20 gallons
Material	Injection-molded structural foam polyethylene, one piece
Rim	Pre-drilled holes with metal inserts to accept a cover
Sealing	Gas and radon tight when fitted with a sealed cover
Weight	11 lb

This is the part of a horsepower upgrade nobody sells you. Pump capacity and pit volume work together: the pump empties the basin down to its off point, the basin refills, and the pump starts again. Fit a pump that moves nearly 5,000 gallons an hour into a narrow 14 inch pit and it will empty the pit in seconds, stop, and start again almost immediately. Short cycling is how motors and switches wear out early.

A 20 gallon basin changes the arithmetic. Each cycle moves more water, the motor starts fewer times a day for the same total volume, and a long-throw float has somewhere to travel. If you are going to 1 HP because a storm overwhelms your system, the pit is as likely to be the constraint as the pump — what size sump pit works through the numbers, and two sump pumps in one pit covers the other way to add capacity.

What it gets right

• 20 gallons of volume means a high-flow pump can move a meaningful slug of water per cycle instead of switching on and off against a few gallons
• 22 in of depth gives a long-throw switch like the Superior's room to work the way its designer intended
• One-piece injection-molded structural foam polyethylene — no seams to weep
• Pre-drilled rim inserts take a sealed cover, so the pit can be made gas and radon tight later without replacing the basin
• 11 lb, so one person can place it
• Cheap next to any pump on this page, and it outlives every pump you will put in it

Where it falls short

• Fitting a bigger basin means breaking out the slab around the existing pit, which is a serious job and the reason most people do not do it
• An 18 in basin will not fit every existing hole, and widening a hole in a structural slab is not a casual afternoon
• A deeper pit sits lower in the water table, so in a wet lot it may fill faster once it is in
• Jackel publishes dimensions and material but no drawdown or cycle figures, so the sizing argument stays qualitative

Specifications from 18 x 22 in radon sump basin distributor listing.

Why the 1 HP class is so thin

It is worth understanding what you are shopping in. Residential sump systems are engineered around a pit a few feet deep and a discharge that rises about ten feet, and that job is comfortably inside a 1/3 to 3/4 HP envelope. Above it, demand comes mostly from commercial dewatering, sewage and effluent work, where the pumps are built to different standards, usually discharge at 2 inches or more, and often need a control panel rather than a plug.

That leaves a narrow consumer band, and it has two traps. The first is horsepower labeling on marketplace listings: we found the same model number described as 1 HP by mainstream retailers and as 1/3 HP cast iron by resellers. The second is pumps that are genuinely 1 HP but built for sewage or effluent — excellent machines doing a different job, with solids handling and basin requirements that do not suit a sump pit. If you are comparing a sump pump against something described as an ejector, sump pump vs sewage ejector is the page that separates them.

Sizing: measure lift, not floor area

Pump capacity gets sold by basement square footage, which is close to meaningless — a dry 2,000 square foot basement needs less pump than a wet 800 square foot one. Three measurements decide it:

1. Vertical lift. From the pump's off point in the pit to the highest point the water has to reach in the discharge line. Measure it rather than estimating from the ceiling height.
2. Pipe run and fittings. Every elbow and every foot of horizontal pipe adds friction that the pump experiences as extra height. A long run to a legal discharge point can add several feet of effective head.
3. Inflow in a storm. With the pump unplugged, time how long the pit takes to rise a measured number of inches during heavy rain, and convert that to gallons per hour using the basin's dimensions. That is the only number that tells you whether the pump is actually outmatched. How often should a sump pump run gives the baselines.

Add the first two to get total dynamic head, then read across a published flow curve at that head. If a 3/4 HP pump still clears your storm inflow at your head, buy the 3/4 HP pump. The whole method is in what size sump pump do I need and how to choose a sump pump.