How to unblock a sink

In a hurry? Watch our short video guide instead.

If it looks like your sink might be blocked – don't worry. It’s one of the most common household problems, and it’s usually fairly easy to fix. So you won't always need to call out a professional plumber.

3 top tips for unblocking a sink

Our guide will help you unblock your sink using things you might already have at home. And we'll share our top tips on how to avoid a blocked sink in future.

If you've tried these steps and nothing seems to work, you can call us to fix it for you. We’ll set you up with our most comprehensive plan and repair your blocked sink, as part of our Home Recover¹ service.

1. Pour boiling water down the sink

If you've handled blocked drains before or you’re an experienced DIY-er, you'll know that boiling water can work wonders. It’s probably the easiest, cheapest way to try and unblock your sink.

When boiling water flows through your pipes, it can gently loosen blockages made up of grease, residue, or leftover food. So just follow these steps to give it a try:

1. Fill a whole kettle and boil it. Or boil a pot of water on the stove.
2. While you're waiting for it to heat up, remove as much leftover water from the sink as you can, using a cup or a pot.
3. Carefully pour the boiling water into the sink and wait a few moments.
4. If the water doesn’t drain away, give it time to cool. Or if you see signs of improvement but there’s still a blockage, remove the water once it’s cooled and repeat these steps.

You might need to try this a few times to fully remove the blockage. If it’s not improving, you can move on to our next method if you feel comfortable.

2. Use baking soda or effervescent tablet and vinegar

Here’s another natural method that can really work – without using chemicals. You might already have these ingredients at home, so it’s worth giving it a go. Just follow these steps:

1. Remove any water from the sink using a cup or pot.
2. Drop between half a cup and 1 cup of baking soda into the plughole. As soon as you've added the baking soda, pour a cup of white vinegar down the sink. Wait for the chemical reaction to take place – you’ll hear it start to bubble.
3. Fill a whole kettle and boil it. Or boil a pot of water on the stove.
4. Carefully pour the boiled water down the sink. You might need to do this a few times to get rid of any leftover waste.

3. Unblocking your sink with a plunger

No luck? Our final tip is to try and remove the blockage with a plunger. In this case, we’d recommend using a flat-bottomed one. Here are the steps to follow:

1. Pour hot water into the sink until it's roughly half full.
2. Place the plunger over the entire plughole to create a secure seal.
3. Quickly pump the plunger up and down, as many times as you need to. And be careful not to splash hot water.
4. Gently remove the plunger and wait for the water to drain away.
5. If the water has drained, flush the sink with hot water from the tap or kettle. If your sink is still blocked, try repeating these steps.

Or we can fix it for you

We know taking out cover isn't for everyone. But at OVO, we think you should still get the best support when problems happen.

That’s why, if you don’t have cover, we can set you up with our most comprehensive plan and repair your blocked sink. It’s called Home Recover.

About Home Recover

If you’re an OVO customer and something’s gone wrong, we’ll fix the problem for free when you take out our Complete plan. And even if you’re not with us, we’ll fix your blocked sink for a £79 fee when you sign up to our Complete plan. Just give us a call on 0330 102 8905 or visit our website to get started.

Our Complete plan has you covered, whether it’s a blocked sink, or a problem with your boiler, gas pipes, or drains. All our plans come with unlimited call-outs, access to a network of Gas Safe engineers, and a 24/7 emergency helpline.¹

How to prevent a blocked kitchen sink

When you’re throwing away waste at home, here’s what you should try and avoid putting down the sink:

• Fat, oil, or grease. Instead, collect it in disposable packaging, secure it once it’s full, and put it in your general waste bin.
• Meat. It should really go in your food waste bin, and scrape off any scraps before washing up your plate.
• Coffee grounds. These are a big culprit when it comes to blocked sinks. But luckily, they can be easily composted or go into your food waste bin.
• Starchy foods. Again – food waste or compost.
• Fruit peel. It’s also easy to compost.
• Paper products, like kitchen roll. Recycle it or if it’s used, put it in general waste.