Sump Pump Not Working? 7 Fixes to Try Right Now
Before paying for a service call, run through these diagnostic steps. Many sump pump failures have simple causes you can fix in under 10 minutes — for free.
Quick safety note
If your basement is actively flooding, stop reading and call an emergency plumber now. If water is near outlets or electrical panels, do not enter the water. Turn off the circuit breaker to the basement first.
The 7 Fixes (Try These First)
Check the Power Supply
This sounds obvious but it is the cause of roughly 20% of "broken" pump calls. Check three things: (1) Is the pump plugged in? The outlet under a utility sink or on a basement wall can get accidentally unplugged. (2) Is the outlet working? Plug in a lamp or phone charger to test it. (3) Is the circuit breaker tripped? Open your panel and look for a breaker labeled "basement," "sump," or "utility" that is in the OFF position or stuck in the middle.
✓ Free fix — takes 2 minutes
Reset the GFCI Outlet
In many homes, basement outlets are GFCI-protected (Ground Fault Circuit Interrupter). You can identify them by the TEST and RESET buttons on the outlet face. Moisture — even humidity — can trip a GFCI without triggering the main breaker panel. Find the GFCI outlet your pump is connected to and press the RESET button firmly. You should hear a click. Then test your pump.
✓ Free fix — takes 1 minute
Free the Float Switch
The float switch is a buoyant arm or ball that rises with the water level and triggers the pump to turn on. When it gets tangled around the discharge pipe or pressed against the pump housing, it gets stuck and stops working. Look into the sump pit and check that the float arm or ball can move freely in all directions. If it is tangled or caught, gently free it. Then pour a bucket of water into the pit to test if the pump activates.
✓ Free fix — takes 5 minutes
Clear Debris from the Pit
Rocks, gravel, sand, and even small toys can find their way into the sump pit and jam the impeller — the spinning component that moves water. With the pump unplugged, reach into the pit (wearing gloves) and clear any debris you see. If the pit has significant sediment accumulation, scoop it out with a bucket. Reconnect power and test. You may also hear the motor hum without the pump moving water — this typically means impeller jam.
✓ Free fix — takes 10–20 minutes
Check the Discharge Pipe
Your pump may be running but unable to move water because the discharge pipe is blocked or frozen. Follow the discharge pipe from the pump to where it exits your home. Check the exterior termination point for a blocked opening, ice plug in winter, or visible damage to the pipe. A blocked discharge pipe causes the pump to cycle on and off rapidly without reducing the water level in the pit.
✓ Free fix (if just blocked) — takes 10 minutes
Test Manual Activation
To isolate whether the problem is the float switch or the motor, test manual activation. With the pump plugged in and the pit empty, pour water in slowly while holding the float arm up with a stick. If the pump activates, your motor is fine and only the float switch needs replacement (a $100–$200 repair). If it doesn't activate with the float held up, the motor or electrical system is the problem.
Diagnostic step — helps identify the repair needed
Listen and Smell the Motor
With the pump plugged in and water in the pit, listen carefully: A humming sound with no water movement means power is reaching the motor but the impeller is jammed or seized — the motor or capacitor may need replacement. Complete silence usually means an electrical problem (failed capacitor, broken wiring). A burning smell is a dead motor. These diagnoses help you communicate with a contractor and avoid being oversold.
Diagnostic step — helps communicate with a pro
When to Stop DIYing and Call a Pro
- ● Your basement is actively flooding right now
- ● You smell burning from the motor (motor has failed — don't leave it plugged in)
- ● You've tried all 7 fixes and the pump still doesn't work
- ● Heavy rain is forecast in the next 24 hours
- ● Any repair involving wiring, motor components, or capacitors
- ● The pump is more than 7 years old (it's time for proactive replacement anyway)
What Repair or Replacement Costs
See our full sump pump cost guide for city-by-city pricing.
Frequently Asked Questions
Why is my sump pump not working? ▼
The most common causes are: tripped circuit breaker, stuck float switch, jammed impeller from debris, failed motor or capacitor, clogged discharge pipe, or a tripped GFCI outlet. Start with the simple checks — about 40% of "broken pump" calls are resolved with a free fix like resetting a breaker.
Can I fix a sump pump myself? ▼
Safe DIY fixes include: resetting a tripped breaker, pressing a GFCI reset button, freeing a stuck float switch, and clearing debris from the pit. Motor repair, capacitor replacement, electrical repairs, and discharge pipe rerouting should be done by a licensed professional.
How urgent is a non-working sump pump? ▼
Very urgent if rain is expected, or if you live in a flood-prone area. Even in dry conditions, a broken sump pump should be diagnosed within 24–48 hours. A $300 repair done today prevents potentially $10,000 in basement water damage during the next storm.
What does it cost to fix a sump pump that won't turn on? ▼
Float switch: $100–$200. Capacitor: $150–$300. Motor: $250–$450. Full replacement: $400–$1,400 installed. Start with a free AI diagnosis here to know which repair is likely needed before you call anyone.
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