Sump Pump Alarm Going Off
A sump pump alarm sounds when water in the pit rises higher than it should. That usually means the pump is not running, the float switch is stuck, the pump cannot keep up, or the power is off. Check the power and the float right away. Fixes range from free to about $150 to $1,200 for a new float switch or pump.
Typical pro cost
$150 to $1,200
- Urgency
- Fix today
- DIY difficulty
- Moderate
- Time to fix
- 15 minutes to 2 hours
- Prices
- US typical range
Last reviewed October 2026
Signs it's this problem
- A loud beeping from the basement or crawl space
- Water close to the top of the sump pit
- The pump hums but water does not go down
- The pump is silent during heavy rain
Common causes
Power loss
A tripped breaker, GFCI outlet or unplugged cord stops the pump.
Stuck float switch
The float gets caught on the pit wall or the pump cord.
Failed pump
An old or burned-out motor cannot move water.
Clogged or frozen discharge line
Water cannot leave the house, so the pit fills.
Too much water
In very heavy rain, a small pump may not keep up.
How to fix it, step by step
- 1
Silence the alarm and look into the pit to see how high the water is.
- 2
Check that the pump is plugged in, the GFCI outlet has not tripped, and the breaker is on.
- 3
Lift the float gently with a stick. If the pump starts, the float was stuck; move the cord so it cannot catch.
- 4
If the pump hums but does not pump, unplug it and check the inlet screen for debris.
- 5
Outside, make sure the discharge pipe is not clogged, frozen or buried.
- 6
If the pump is dead or over about 7 to 10 years old, replace it. Consider a battery backup pump.
Tools and materials
- Flashlight
- Stick or broom handle
- Gloves
Approximate DIY cost: $0 to $250 (float switch or DIY pump)
Call a pro when
- The pit is overflowing and the pump will not run
- You want a battery backup or second pump installed
- The discharge line is frozen or broken outside
Sump Pump Alarm Going Off cost
| Job | Typical cost |
|---|---|
| Replace a float switch | $150–$350 |
| Replace a sump pump | $400–$1,200 |
| Battery backup sump pump, installed | $500–$1,500 |
| High-water alarm, installed | $100–$300 |
Ranges are typical US prices compiled by FixHomeCost. Prices vary by region, home and contractor, so compare 2–3 local quotes.
Common questions
How do I turn off my sump pump alarm?
Most have a silence button. Turn it off only after you have checked the pump, because the alarm means the water is rising.
Why is my sump pump alarm going off when it is not raining?
Groundwater, a stuck float or a pump that stopped running can raise the water level even without rain. It can also be a faulty alarm sensor.
How long do sump pumps last?
Usually about 7 to 10 years. Test yours each spring by pouring water into the pit.
Should I get a battery backup sump pump?
If your basement floods when the power goes out during storms, a battery backup is worth considering.
Related guides
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