How to Drill a Quartz Countertop


Quartz countertops are engineered stone made from ground quartz crystals combined with resins and pigments. Their hard, non-porous surface makes them popular kitchen countertops. However, their hardness also makes quartz more difficult to cut and drill compared to other stones. With patience and the proper methods, drilling holes in a quartz countertop is quite achievable.

Things You’ll Need

  • Safety goggles
  • N-95 dust mask
  • Ear protection – quartz drilling can be loud
  • Marking pencil or tape to mark drill location
  • Vacuum clamp or C-clamp to secure countertop
  • Variable speed drill
  • Diamond-grit core drill bits specifically for quartz
  • Slide hammer to detach core drill bit
  • Wet sponge
  • Mineral spirits for cleaning drill area

Choosing the Right Drill Bit

Choosing the proper drill bit is crucial for drilling quartz successfully. You’ll need diamond core bits made specifically for quartz or granite. Carbide or steel bits will fracture the stone. For holes smaller than 1/4″, use diamond burr drill bits. For larger holes, use diamond core drill bits with water to keep them cool and lubricated. Match the bit size to the desired hole size.

Marking the Hole Location

Use a pencil or masking tape to mark the desired hole location. Outline the drill area for better visibility. Make sure the location has enough clearance underneath for the drill bit.

Securing the Countertop

Firmly secure the countertop with a vacuum clamp or C-clamp on the area to be drilled. This prevents vibration and slippage as you drill. Ensure the clamping pressure is even over the surface.

Drilling a Pilot Hole

Set the drill to the lowest speed and make an initial pilot hole with light pressure at the marked location. Use a 1/8” masonry bit to make the pilot hole before using larger diameter bits. The pilot hole guides the core drill accurately.

Drilling the Main Hole

With the pilot hole made, switch to the quartz core bit matched to the desired hole size. Apply firm, even pressure in a straight up and down direction. Do not wobble the drill. Use water to keep the bit wet and cool if needed.

Drill slowly and steadily through the stone thickness. Periodically lift the bit to allow stone dust to clear.

Finishing the Drilled Hole

Once the full depth is reached, stop drilling and detach the core bit. Insert a screwdriver in the drilled hole and tap firmly with a hammer to loosen the circular core. Wiggle it free from the underside.

Smooth rough edges around the hole with a file or sandpaper. Flush the area with water to remove stone dust. Use mineral spirits to clean oil left from the drill bit.

The hole is now ready for insert installation or plumbing fittings.

Tips for Drilling Quartz Countertops

  • Allow new quartz counters 1-2 weeks to fully cure before drilling holes
  • Always use sharp, high-quality diamond core bits designed for quartz
  • Drill slowly with firm, even pressure – never force the drill
  • Minimal speeds under 300 rpm work best to avoid cracking
  • Periodically lift drill bit to clear away dust for smoother drilling
  • Use lubricating water and pauses to prevent overheating drill bits
  • Higher bit speeds can be used on softer quartz varieties like Caesarstone
  • Clamp a wood block beneath as backing support when drilling through shallow countertops

Frequently Asked Questions

What size diamond core bit do I need for a 3/8″ faucet hole?

Use a 1/4″ diamond core bit for a 3/8″ faucet hole. Match the bit diameter to the hole size needed.

Can I use a regular masonry drill for quartz?

No, masonry drill bits will crack and chip quartz. You need special diamond core bits designed for quartz and granite.

Is drilling quartz dangerous?

With proper precautions, drilling quartz is safe. Always wear safety goggles and a dust mask. Proper drilling technique prevents cracking.

How can I smooth rough edges around the hole?

Use a file or sandpaper around the cut surface to smooth out any rough edges or lips left from drilling.

What speed should I drill quartz at?

Ideal speeds for quartz are 200-300 rpm. Start at the lowest speed and adjust as needed. Higher speeds can overheat and damage bits.


Drilling into quartz counters is made easier using diamond core bits, taking precautions against cracking, and drilling with controlled speed and pressure. With the proper methods, holes for faucets and other inserts can be added post-installation for a fully functional quartz countertop. Just have patience and allow time for the process. And soon you’ll have the customized quartz countertop you desire.