How to Unblock a Sink

Why Sinks Block

Kitchen sinks block from grease, fat, and food debris building up in the pipe over time. Bathroom sinks block from hair, soap scum, and toothpaste residue. Both types respond to the same basic methods.

Method 1 — Boiling Water

The simplest first attempt: slowly pour a full kettle of boiling water down the drain in 2-3 stages, allowing it to work for a few seconds between pours. This melts grease and soap blockages in many cases.

Method 2 — Bicarbonate of Soda and Vinegar

Pour half a cup of bicarbonate of soda down the drain, followed by half a cup of white vinegar. Cover the drain immediately. Wait 15-20 minutes then flush with hot water. Excellent for organic blockages.

Method 3 — Plunger

Place a cup plunger firmly over the drain hole. If it is a double sink, block the other drain with a cloth. Push down firmly then pull up sharply. Repeat 10-15 times with a firm rhythmic action.

Method 4 — Clean the P-Trap

The P-trap is the curved pipe section under the sink. Place a bucket underneath, unscrew the trap by hand or with pliers, and clear any blockage. This is the most reliable fix for stubborn sink blockages.

Preventing Future Blockages

Use a sink strainer to catch debris, never pour cooking fat down the drain, run hot water for 30 seconds after washing dishes, and do a monthly bicarbonate and vinegar flush to keep drains clear.