Sump pump not running?

A sump pump that won't run is often just unplugged or on a tripped GFCI or breaker, or its float switch is stuck. If the basement is already flooding, don't step into the water: it can reach outlets and cords.

Not sure which one it is? Snap your sump pump and we’ll narrow it down.

Is the pump running too much instead of not at all?

That's a different problem, and it has its own causes. Sump pump runs constantly

Likely causes

  1. No power (unplugged, tripped GFCI or breaker)

    Most commonEasy DIY

    The pump is silent with no hum, even with water high in the pit. The cord has been knocked loose, or the GFCI outlet it plugs into has tripped, or a breaker has. Only reset a GFCI or breaker if you can reach it from a dry spot.

  2. Stuck float switch

    CommonModerate DIY

    Water rises in the pit but the pump never starts. The float is caught on its own cord or the pit wall, or jammed by debris. Unplug the pump before you reach in to free it.

    Part: $75–125 (float switch repair), $100–150 (replacement)

  3. Jammed impeller or clogged intake screen

    CommonModerate DIY

    The pump hums or runs but moves little or no water. Stones or debris can block the intake screen or jam the impeller. Unplug it before you reach in, and wear gloves.

  4. Frozen or clogged discharge line

    CommonModerate DIY

    The pump runs but water isn't leaving, or it comes out only slowly. Check where the discharge pipe exits outside for ice or a blockage.

  5. Failed motor

    Less commonCall a pro

    Power is fine and the float works, but the pump makes no hum at all when it should start. A burned-out motor needs a repair or a new pump.

    Part: $150–300 (motor repair), $250–500 (replacement)

  6. An old pump

    Less commonCall a pro

    The pump is around 10 years old or more and has started to fail or run poorly. HomeAdvisor puts a pump's lifespan at about 10 years with maintenance.

    Part: $800–2,000 (submersible, installed), $400–600 (pedestal, installed)

Quick checks

If the basement is flooded, don't step into water that could touch outlets or cords. Turn the power off at the breaker only if you can reach the panel from a dry spot; otherwise call an electrician or the utility. Unplug the pump before reaching into the pit, don't run the pump from an extension cord, and wear gloves, because pit water can be dirty.

  1. If the basement floor is wet, don't step into water that could touch outlets or cords. If you can reach the electrical panel from a dry spot, turn the power off at the breaker; if you can't, call an electrician or the utility.
  2. Check that the pump is plugged in, and that the GFCI outlet it uses hasn't tripped (press Reset on the outlet) or a breaker hasn't flipped. Plug the pump directly into the wall outlet, never an extension cord.
  3. Unplug the pump before reaching into the pit, and wear gloves, because pit water can be dirty.
  4. Look at the float: make sure it moves freely and isn't caught on the cord, the pit wall or debris.
  5. Pour a bucket of water into the pit to see whether the pump starts. If it hums but doesn't pump, unplug it and check the intake screen for debris.
  6. Check the discharge pipe outside for ice or a blockage. If the pump runs without pause instead, see sump pump runs constantly.
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Snap one of these:

  • the pump and float in the pit
  • the discharge pipe and check valve
  • the outlet the pump plugs into
  • the pit water level

Add a note or more photos next. Nobody calls you.

When to call a pro

Water is standing in the basement and you can't safely reach the outlet or panel, the pump has power and a free float but still won't run, the motor is dead, or the pump is old enough that replacing it makes more sense than another repair. HomeAdvisor puts a sump pump repair at an average of $531 ($309–755). A battery backup replacement is $250–500. For a pump that never stops, see sump pump runs constantly. For upkeep, see the sump pump guide.

Typical cost: HomeAdvisor puts sump pump repair at an average of $531 ($309–755). A float switch repair is $75–125 and a replacement $100–150. A motor repair is $150–300 and a replacement $250–500. A battery backup replacement is $250–500. A new pump installed runs $800–2,000 for a submersible and $400–600 for a pedestal. A pump lasts about 10 years with maintenance.

Sources: HomeAdvisor: How much does sump pump repair cost? (updated June 17, 2026)

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