Should you repair or replace your sump pump?
Updated August 2026
← Every repair-or-replace call
Replace a sump pump once it reaches 7–10 years or the motor burns out; only a stuck float, a failed check valve, or a clogged intake is worth repairing, and those run $20–150. The economics are blunt. A new 1/3 hp cast-iron pump is $150–350 dropped in yourself and $400–750 installed, so paying a plumber to chase an old motor makes no sense. What sharpens the decision is what the pump protects. A unit that quits during a spring storm becomes a flooded basement, and those cleanups reach $10,000–30,000 once finished space is involved.
The short version
Treat a sump pump as a consumable with an expiration date, not a machine you rebuild. Seven to ten years is the service window, and the failures that end it, seized bearings and burned windings, cost more in diagnostic labor than a new pump costs outright. Repair the accessories only: a float tangled against the pit wall, a check valve letting water fall back so the pump cycles itself to death, or a screen packed with silt. Because the downside of failure is measured in five figures, timing beats arithmetic here. Swap the pump on schedule and on a dry day, ahead of the wet season, and add a battery backup for $150–400 so a power cut during the storm is not the failure mode.
Your situation, decided
| Situation | Verdict | Why |
|---|---|---|
| Pump runs but the water keeps rising | Repair | Usually a stuck check valve or a clogged intake, $20–150 |
| Will not start, float hung on the pit wall | Repair | A $20–60 float switch, or simply re-hang the tether |
| Motor hums and trips with the impeller free | Replace | Burned windings; a $150–350 pump beats a rebuild |
| Pump is 7–10 years old and still working | Replace on schedule | Deep in the failure range; do it dry, not during a storm |
| Cycles on and off every minute | Repair | A failed check valve or an undersized pit, not a dead pump |
| Finished basement with no backup pump | Add a backup | A $150–400 battery pump against a $10,000–30,000 flood |
What each path costs
Repairs typically run $20–150; a replacement is $400–750 installed. A sump pump lasts 7–10 years, less if it runs most of the year. Replace on age alone rather than waiting for the storm that finds the weak motor. Price your own number on the home maintenance cost calculator before you commit either way.
The repair-or-replace call is easy when you know the unit's age and service history. OnOtto keeps both, plus the maintenance that delays this decision for years.
Start your home's service log, freeFrequently asked questions
How do I test a sump pump?
Pour water in; do not just flip the switch. Carry five gallons into the pit and watch three things: the float rises and the pump starts within a few seconds, the level drops quickly, and the check valve thumps shut when the motor stops. If the pump runs but the level barely moves, the discharge is clogged or frozen outside. Do this every three months and again before the wet season. Watch the silt too, because a packed pit is what jams floats.
Is a battery backup sump pump worth it?
With a finished basement, it is the cheapest insurance in the house. Storms take out power at the exact hour the pit is filling, and the primary pump is scrap metal on a dead circuit. A DC backup pump and battery cost $150–400 for the hardware and $700–1,500 professionally installed with a quality battery. The battery is itself a wear part on a 3 to 5 year clock, so put the battery swap on a schedule or the backup fails silently.
Why does my sump pump run all the time?
Usually water arriving that should never reach the pit. Downspouts discharging beside the foundation, a high water table after snowmelt, and grading that slopes toward the house all feed it continuously. A failed check valve does the same by letting the water in the discharge pipe fall back after every cycle. Constant running burns through the 7 to 10 year life in a hurry. Fix the drainage outside first, since regrading and extending downspouts is cheaper than a bigger pump and a shorter replacement cycle.
Can I replace a sump pump myself?
Most people can. Unplug it, unthread the discharge union, lift the old pump out, and set the new one on a brick or a flat pit bottom so it does not draw silt. Reuse or replace the check valve, confirm the float has clearance on every side, then test with five gallons. Budget $150–350 and about an hour. Hire it out if the pit has no union, the outlet is not a dedicated GFCI circuit, or the discharge needs rework, which is where the $400–750 installed price comes from.