Overflowing Toilet or Sewage Backing Up: What to Do

Toilet overflowing or sewage coming up? Stop it, protect your home and stay safe until a plumber arrives. Call 020 8050 9933, open 24/7.

Key facts

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An overflowing toilet or sewage coming up through drains is unpleasant and unhygienic. Acting quickly limits the spread, and a plumber can find and clear the blockage.

Step 1: Stop the flow

Do not flush again. Turn off the toilet's isolation valve if it has one, and stop using sinks, baths, showers and washing machines, which all feed the same drain.

Step 2: Keep people and pets away

Sewage can carry bacteria. Keep children and pets out of the affected area, wear gloves and boots if you have to go in, and wash your hands afterwards.

Step 3: Limit the spread

Mop up small spills with towels or old cloths and place them in bin bags. For larger spills, avoid wading in and wait for help. Open windows for ventilation.

Step 4: Check whether it is just your drain

If neighbours have the same problem, or sewage comes up in several places, the blockage may be in a shared drain or the public sewer. Contact your water company as well as a plumber.

Step 5: Do not use chemical cleaners

Strong chemicals can make it unsafe for the person who clears the blockage and rarely help with a serious backup. Leave it for a plumber with the right equipment.

Step 6: Call for help

Call 020 8050 9933 24 hours a day. A drain survey can show the cause, and high-pressure jetting can clear most blockages.

Quick tips

Related help

Common questions

How much does it cost to clear a blocked drain?

An internal drain unblock is typically £60 - £90 and an external one £80 - £120, including VAT, plus the call-out fee.

Do you do drain surveys?

Yes. A CCTV drain survey is typically £150 - £250 including VAT, plus the call-out fee.

Can you help with a blocked toilet only?

Yes. See our blocked toilet emergency page. We take bookings 24 hours a day, 7 days a week.

Call 020 8050 9933