How to unclog supply line

PlumbingUpdated March 2026

The answer to 'how to unclog supply line' is to use a plunger or snake to dislodge the clog. First, try using a plunger to create suction and force the clog down the pipe. If that doesn't work, use a plumber's snake or auger to physically break up the clog and pull it out. Be sure to wear gloves and eye protection when using these tools.

If the clog is deep in the supply line or you are unable to clear it, it's best to call a professional plumber. They have specialized equipment and expertise to safely and effectively clear tough clogs without causing further damage to your plumbing system.

Sources

International Association of Plumbing and Mechanical Officials (IAPMO)— authority

Plumbing and Drainage Institute (PDI)— authority

This Old House: How to Clear a Clogged Drain— guide

Step-by-Step Guide

1
Use a Plunger
Fill the sink or tub with a few inches of water, then firmly place the plunger over the drain opening. Quickly pull the plunger up and push it down several times to create suction and dislodge the clog.
2
Use a Plumber's Snake
If the plunger doesn't work, use a plumber's snake or auger. Feed the end of the snake into the drain and crank the handle to extend the snake and break up the clog. Retrieve the snake and any debris it pulls out.

Frequently Asked Questions

How often should I check my supply lines for clogs?

It's a good idea to check your supply lines for clogs at least once a year, or more frequently if you notice slow draining or other signs of a potential clog.

Can I use chemical drain cleaners to unclog my supply line?

Chemical drain cleaners can be harsh on plumbing and are not recommended for supply lines. They may cause damage to the pipes or fixtures. It's best to use mechanical methods like a plunger or snake instead.

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