How to Unblock a Kitchen Sink: Safe DIY Steps

Unblock a slow or blocked kitchen sink with a plunger and trap clean, and know when to call a plumber. Call 020 8050 9933.

Key facts

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Most kitchen sink blockages are grease, food and soap building up in the waste pipe or trap. A plunger and a trap clean fix many of them without a plumber.

Try a plunger first

Remove the plug and block the overflow with a damp cloth. Cover the plunger with water and push and pull firmly for about 20 seconds. Repeat a few times.

Clean the trap

Place a bucket under the U-shaped trap, then unscrew it by hand or with a wrench. Clear out any debris, rinse and refit. Wear gloves and expect water.

Flush with hot water

Run hot (not boiling) water to clear loosened grease. Avoid pouring boiling water into plastic pipes or into a cracked or old sink.

Be careful with chemical cleaners

Strong drain cleaners can damage some pipes and are hazardous if they splash. Never mix cleaners, and follow the label. If a cleaner does not work, do not add another product on top.

When to call a plumber

If water drains slowly again soon after, or several fixtures are affected, the blockage may be further along the pipe. An internal drain unblock is typically £60 - £90 including VAT, plus the call-out fee.

Quick tips

Related help

Common questions

Why does my kitchen sink keep blocking?

Grease, food waste and soap are the usual causes. Avoid pouring fat down the sink and use a strainer.

Do you offer drain jetting?

Yes. High-pressure jetting is typically £120 - £200 including VAT, plus the call-out fee.

Is a blocked drain an emergency?

It can be if water is backing up or overflowing. We take bookings 24 hours a day, 7 days a week.

Call 020 8050 9933