Drains & clogs

Utility or laundry sink drains slowly

A slow-draining utility or laundry sink is often clogged with lint, dirt, and detergent residue since it handles heavier, dirtier water than a typical bathroom sink.

Difficulty
Easy
Time
25–45 minutes
DIY cost
$5–$20
Pro cost
$120–$220

Symptoms

  • Water empties slowly after washing tools or clothes
  • Standing water lingers longer than expected
  • Grimy residue visible around the drain opening
  • Slower drainage noticed gradually over weeks

Likely causes

  • CommonLint and detergent residue buildupLaundry sinks especially collect lint that combines with soap into a sludge.
  • CommonDirt or sediment from cleaning tools or paint brushesUtility sinks often handle dirtier water than typical fixtures.
  • PossibleClog in the trapDebris settling in the P-trap under the sink.
  • PossibleShared line clog with a nearby washing machine standpipeIf plumbed together, a clog in one can slow the other.

What to do

  1. Avoid rinsing paint, heavy dirt, or plaster directly down the drain going forward, since these are common causes of buildup.
  2. Plunge the sink drain firmly with the overflow (if present) covered.
  3. Pour a baking soda and vinegar mix down the drain, let sit 15 minutes, then flush with hot water.
  4. If still slow, remove and clean the P-trap under the sink, checking for lint, dirt, or sludge buildup.
  5. For a persistent clog, use a hand-crank drain snake through the trap arm toward the wall.
  6. If the sink shares a line with a washing machine standpipe, check that connection for lint buildup as well.
  7. Run water afterward to confirm normal drainage.

Tools and parts

  • Plunger
  • Adjustable pliers
  • Baking soda
  • Vinegar
  • Hand-crank drain snake

When to call a pro

Call a plumber if cleaning the trap and snaking doesn't restore normal drainage, since the clog may extend further down a shared line.

Safety

Generally low risk

Generally low risk for a careful person. Stop if anything looks different from what this guide describes.

Related guides

Operator provides AI-generated troubleshooting information. It can be wrong. For safety-critical, electrical, gas, structural, medical, automotive safety, or other high-risk problems, consult a qualified professional.