Post By Admin
June 27, 2026Is there water pooling around your kitchen sink? Chances are, you’re dealing with a kitchen sink leak around the edges.
Not only is this frustrating, but it can lead to bigger problems like damaged countertops, mould growth, and even hidden water damage under your sink.
Hence, In this guide, we’ll cover the most common causes, walk you through the fix step by step, and help you figure out when it’s worth calling in a licensed plumber instead. If you suspect the leak has already caused hidden damage, it may be worth looking into our leak detection services before it gets worse.
Common Reasons Why Kitchen Sink is Leaking Around the Edges
When you see your kitchen sink leaking from the top, it’s usually a sign that the water isn’t contained properly between the sink and the countertop.
Ignoring it can quickly turn into costly repairs. Understanding the root cause is the first step toward a long-lasting fix.
1. Leaking Faucets
One of the easiest things to overlook is a dripping tap because even a small drip can build up around the sink rim over time and slowly work its way underneath.
You might think that a failed sink seal caused the constant moisture near the tap base. But it’s more likely you’re dealing with a leaking tap handle or a leaking mixer tap.
2. Damaged or Missing Sealant
When the silicone sealant around your sink starts to crack, shrink, or peel away, it leaves gaps where water can easily sneak through.
Without a tight waterproof barrier, water collects and spills under the countertop, causing that telltale sink leak.
3. Improper Installation
Another major reason for a kitchen sink leaking is poor installation. If the sink wasn’t properly secured or sealed when first installed, the slight movement from daily use can cause gaps to form between the sink and the counter.
This is especially common with undermount sinks, where invisible mounting problems are harder to spot right away. You can also check back on our tips for installing a kitchen sink to understand how to do it properly.
4. Loose Clips or Hardware
A leaky kitchen sink can also happen if the metal clips or brackets holding it in place become loose over time. As these parts shift (even slightly), it can break the seal and allow water to get under the edge.
So, always check under your sink for any missing or loose hardware if you’re trying to figure out why your sink is leaking.
5. Your Existing Sink Type
With drop-in (top-mount) sinks, the silicone around the visible rim is usually the problem.
Meanwhile, with undermount sinks, the bond underneath the benchtop is more likely to fail, which can be harder to spot until water starts showing up below.
What You’ll Need
Before you start, get your tools ready so that it will make the job much smoother.
For most kitchen sink reseals, you will need:
- Utility knife or scraper
- Painter’s tape (blue masking tape works well)
- Rubbing alcohol or sugar soap
- Clean cloths or paper towels
- Mould-resistant silicone sealant (Selleys Wet Area Silicone or Parfix Wet Area Silicone from Bunnings are solid options)
- Silicone gun
- Plastic smoothing tool or your finger
- Screwdriver for tightening mounting clips
How to Fix a Kitchen Sink that Leaks Around the Edges
Once you know why your kitchen sink is leaking, the fix is usually simple. Here’s exactly what you need to do.
Step 1: Find the Leak Source
Start by drying the entire sink area thoroughly. Then run water along the faucet, the corners of the sink, and the edges while observing closely.
Watch for any bubbling, pooling, or trickling water that can help you spot the exact location of the kitchen sink leak from the top. This step is crucial because fixing the wrong spot won’t solve your problem.
However, if you find the leak coming from pipes underneath, you can check out our guide on how to fix a leaking pipe.
Step 2: Remove Old Sealant
If the leak is caused by deteriorating sealant (which it often is), you’ll need to carefully remove all the old material. Using a utility knife or scraper, gently peel away any cracked or mouldy silicone from around the sink edge.
Once removed, clean the surface thoroughly using rubbing alcohol to get rid of grime or grease. For the new sealant to bond well, the area must be completely clean and dry.
Step 3: Apply New Waterproof Sealant
Choose a high-quality, mould-resistant silicone sealant designed for kitchens and bathrooms.
Then, apply a steady bead of silicone all around the edge of the sink where it meets the countertop. Work slowly to keep the line even.
Finally, use a wet finger or caulking tool to smooth out the sealant, pressing it firmly into the gaps. This will create a watertight barrier that prevents future sink leaks and stops your kitchen sink from leaking once and for all.
Step 4: Tighten Sink Mounting Brackets
If your sink installation hardware is loose, take this opportunity to tighten it. Grab a screwdriver and make sure all clips are securely fastened.
The sink should sit evenly against the counter, with no visible gaps. If you skip this, you might see your kitchen sink leak again even after resealing.
Step 5: Allow Proper Curing Time
After sealing, patience is key. Allow the silicone to cure completely (usually 24 hours) before using the sink again. Rushing this step will compromise the seal and could lead to the same kitchen sink leaking problem all over again.
Step 6: Test for Leaks
Once cured, fill the sink with water and leave it sitting for 5–10 minutes.
Then, check underneath and around the edges for any moisture. If you still see water, the seal may not have bonded correctly, which can be your cue for going for another re-attempt or calling a plumber.
How to Prevent Your Kitchen Sink Leaking Again
Once it’s fixed, follow our experts’ tips for a little maintenance that can go a long way:
- Check the silicone every 12 months for cracks, mould, or lifting.
- Wipe down the sink rim regularly (especially around the tap base where water tends to sit.)
- Avoid abrasive cleaners near the seal because they can weaken it over time.
- Check the mounting clips underneath once a year to make sure they’re still firm.
- The second you notice the sink shifting when you lean on it, reseal it early.
When Should You Call Our Plumber?
If the kitchen sink leaking issue keeps coming back after two attempts, there’s usually something else going on. Place your best bet in hiring plumbing’s service if:
- There’s mould or soft cabinetry under the sink.
- The sink flexes or moves when pressed.
- The mounting points are cracked.
- The leak is coming from the drain flange or pipes.
- There’s water inside the cabinet and you can’t trace the source.
If you’re based in Melbourne and the leak keeps coming back, Neighbourhood Plumbing can inspect the problem properly. Our plumbing services can handle everything from reseals to full leak detection services and larger plumbing repairs. Call us on 0488 885 12!
FAQ About Kitchen Sink that Leaks Around the Edges
Got more questions? Here’s what people often ask about a leaky kitchen sink.
How to seal the edges of a kitchen sink?
You’ll want to remove all the old sealant, clean the area thoroughly, and apply a new bead of waterproof, flexible kitchen silicone around the sink. Smooth it down neatly to create a watertight barrier.
What sealant to use around a kitchen sink?
Use 100% silicone sealant labelled for kitchens or bathrooms. It should be waterproof, mould-resistant, and flexible to handle the daily expansion and contraction that sinks experience.
What is a drip edge on a sink?
A drip edge is a tiny ridge built into some sinks or counters that redirects water away from the sink opening, helping to prevent leaks and pooling. It’s an extra line of defence against a kitchen sink leak.
However, if the leak is coming from underneath instead, you might need to fix a leaking kitchen sink pipe.
Conclusion
Catching a kitchen sink leak early can save you a world of trouble, and now you know exactly what to look for and how to fix it yourself.
However, if you need a professional hand, feel free to contact our experts at Neighbourhood Plumbing.
With years of experience, our team will have your sink back in perfect shape in no time. So, if you have any plumbing issues, give us a call today!
About the Author
From unclogging the toughest drains to repairing leaking toilets, Ricky is a seasoned plumber who has brought his craftmanship to homes across Melbourne. He is passionate about sharing plumbing tips just as much as he is about fixing your plumbing issues. So, when your taps or pipes begin leaking, you know who to call.
