Best Submersible Sump Pumps (2026)

The Mighty-mate is the archetype of the cast iron submersible. The motor, switch case and pump housing are all iron, so the whole assembly acts as a heat sink in the pit water, and the vortex impeller sits recessed from the flow path so it passes small debris without chewing itself up. That combination is why contractors have specified it for decades.

The trade is that 1/3 HP is the smallest motor in a group that includes 1 HP and 1.6 HP hose-kit pumps. If your pit is deep and the discharge climbs a long way, the Zoeller can be outrun on paper by units like the Lanchez 1.6 HP at 6,000 GPH. On a real pit, though, cooling and switch reliability decide survival more than rated flow.

Ownership means fewer surprises. Keep the pit free of gravel, check the float annually and replace the check valve on schedule. It is a pump you buy once, which is the best argument for its higher cost.

The CDU800 pairs a 1/2 HP motor with a cast iron and stainless body and a vertical float switch rated for one million cycles. That number is unusual, because most manufacturers say nothing about switch life, and the switch is the part most likely to leave a pit flooded.

Against the Zoeller M53 at 1/3 HP, the Wayne gives you more motor and a stated cycle rating at a lower price. Against the Lanchez 1.6 HP at 6,000 GPH, it moves less on paper but is built as a pit pump rather than a drain pump. The vertical float also fits narrow pits where a tethered float would hang up on the wall.

At three years the warranty is shorter than the CDU980E's five, so this is the value pick rather than the premium one. Clean the screen, test the float and check valve twice a year, and it is a sound primary.

This is the big number in the lineup, a 1.6 HP motor in a full stainless casing, rated at 6,000 GPH with a 1-1/2 inch discharge that can actually carry it. The stainless body will not corrode, and the integrated float starts the pump at a minimum water level of about 5.3 inches.

That start level is the catch for a pit pump. The pump will not begin until water is above roughly five inches, and it will leave some water behind. A big motor also pulls substantial current at startup, so it needs a properly sized circuit. Compared with the Wayne CDU800 at 1/2 HP, the Lanchez moves more on a hose and less on a documented service record.

It is best as a heavy drain and transfer pump or a pit pump in a large flood-prone space. For a quiet residential pit, the iron pumps are the better long-term bet.

The SEESII is built around a 36 foot lift rating and a 23 foot hose, which makes it a good fit for draining a window well or cellar to a distant or elevated spot. The built-in filter bag keeps small debris out of the pump, and the 1 HP motor gives it reasonable muscle.

The 36 foot figure is a maximum head at which flow reaches zero, not a number at which it pumps well, so real output at a 10 foot rise will be a fraction of the 4,755 GPH label. Against the AQUASTRONG-style 1 HP utility pumps it is similar; against the Zoeller M53 it trades a lot of durability for a lot of rated horsepower.

Treat it as a flexible portable. Use it for flooded areas and pools, and keep the filter bag clean because a clogged bag chokes the intake.

The Superior 91250 is a modest 1/4 HP thermoplastic utility pump that moves up to 1,800 GPH and can lift water up to 25 feet. A 1-1/4 inch NPT discharge and a garden hose adapter make it easy to set up for a window well, a stock tank or a hot tub drain.

It is not a primary basement pump. A 1/4 HP motor has little margin when a storm fills the pit fast, and the thermoplastic body sheds heat less well than the Wayne CDU800's iron one. For a small, dry pit that sees a few inches of water a year, it is adequate and cheap.

Its best role is a second pump: keep it on a shelf with a hose and it saves a flooded floor if the primary dies.

The 6699 is the cheapest pump in the group, a 1/4 HP thermoplastic unit rated at 1,500 GPH with a corrosion-resistant shell and both a 1 inch and a 3/4 inch garden hose adapter. It is the pump you buy to drain a tub, a flooded patio or a shallow window well.

Compared with the Superior 91250 at 1,800 GPH and 25 foot lift, it gives up flow and name recognition for a lower cost. Neither is a pit pump you can rely on during a prolonged storm, and the 1,500 GPH rating falls quickly with any lift.

Buy it for occasional use, check the float and strainer before each job, and do not leave it as the only protection for a finished basement. The thermoplastic shell is light enough to hang from its own hose or cord for short jobs. Store it dry and upright after use so the float and seals are not left sitting in silt.