Why Is My Solid Wood Worktop Turning Black Around the Sink?
For dark grey or black staining developing in a timber worktop around a sink, tap or other regularly wet area.
What this usually means
Black staining around a wooden sink area usually means water has repeatedly penetrated the finish and reacted with the timber, often because the oil finish is overdue, damaged or stripped by strong cleaners. Keep the area dry and first check for a tap or sink leak. Light recent staining may be removable by cleaning or carefully refinishing the surface, but deep black marks, soft timber or swelling indicate more serious moisture damage. Re-oiling only works after the cause and any deep damage are dealt with.
What may be causing this
The protective oil finish has worn thin
Clues: Water stops beading on the surface and dark marks form where splashes sit.
What to do: Dry the area and restore the finish after the staining is treated.
A sink or tap leak is keeping the timber wet
Clues: Darkening is concentrated at one wet edge and moisture is also visible below.
What to do: Repair the leak before refinishing the worktop.
Strong cleaners have stripped the protective finish
Clues: The surface has become dull and absorbs water more readily after chemical cleaning.
What to do: Use appropriate timber-worktop products and restore the finish after drying.
How to check what is happening
The protective oil finish likely needs renewal.
An active leak is causing ongoing damage.
Damage is deeper than a surface stain and may need repair or replacement.
Can you fix this yourself?
Drying, identifying leaks and routine re-oiling are reasonable if the timber remains sound. Deep staining, rot or sink removal is better handled by a fitter or joiner.
- Dry cloth
- Fine abrasive only if manufacturer guidance permits
- Approved worktop oil
What you can safely try
- 1
Stop the moisture source
Repair leaks and wipe standing water promptly.
- 2
Let the timber dry fully
Do not trap moisture under fresh oil or sealant.
- 3
Assess whether the mark is superficial
Surface staining may be refinished; soft or swollen timber needs professional assessment.
- 4
Restore the protective finish
Follow the worktop manufacturer's sanding/oiling guidance once the timber is dry and sound.
Call a kitchen fitter if…
- The timber is soft, rotten or structurally weakened around the sink.
- A sink or tap is actively leaking into the cabinet below.
- Removing the sink is required to reach the damaged edge.
Get the right professional.
This problem can have more than one cause. Start with the checks above: a kitchen fitter is the usual first route, while a plumber may be more appropriate when the clues point that way.
Sources used for this guide
We prefer primary UK guidance, regulators and manufacturers for technical and safety-sensitive claims.
- My solid wood worktops have developed a few stains around the sink area – am I doing something wrong?Worktop Express
- Removing Stains and Discoloration on Wooden Work SurfacesWorktop Express
Last reviewed: 4 September 2026. Home Manual updates review dates only when the substance of a guide is checked or changed.