How to Fix a Crack in a Quartz Countertop

Quartz countertops are popular in many homes due to their durability, aesthetic appeal, and low maintenance. However, like any other countertop material, quartz can develop cracks over time. Cracks in quartz countertops not only look unsightly but can also harbor bacteria and dirt. Fortunately, there are several effective methods to repair cracks in quartz countertops and restore their smooth finish.

Assessing the Crack

Before attempting to fix a crack in a quartz countertop, you need to assess the extent of the damage. This will help determine the best repair method to use. Here are some things to check:

  • Location – Note where the crack is located on the countertop. Cracks near edges or cutouts may require extra reinforcement.
  • Length and width – Measure the length and width of the crack in millimeters. Narrow hairline cracks under 2mm wide can often be repaired more easily than wide cracks.
  • Depth – Check if the crack penetrates deep into the thickness of the countertop or is just superficial on the surface. Deep cracks are more challenging to repair.
  • Edges – Examine the edges of the crack. Jagged, uneven edges will require filling and smoothing.
  • Direction – Determine if the crack runs parallel or perpendicular to the countertop edge. This impacts the repair technique.
  • Cause – Think about what caused the crack, such as impact, heat, or settling. This can help prevent future cracks.

Once you’ve assessed the specifics of the crack damage, you can decide on the best method to repair it.

Cleaning the Crack

Before repairing a crack, it’s important to clean out any dirt, debris, or old sealant from inside the crack. Here is a step-by-step guide:

Materials needed:

  • Soft brush or toothbrush
  • Mild soap and warm water
  • Clean cloth or microfiber towel


  1. Mix a mild soap with warm water in a bowl. Avoid harsh chemicals.
  2. Use the soft brush to gently scrub inside the crack, cleaning out any dirt or residues.
  3. Wipe over the area with a clean damp cloth to rinse off any soap.
  4. Allow the crack to dry fully. Use a hairdryer on a cool setting to speed up drying.

Thoroughly cleaning and drying the crack will allow sealants and fillers to adhere properly, creating an effective quartz countertop crack repair.

Repairing Hairline Cracks

For small, hairline cracks less than 2mm wide, you can often achieve an invisible repair using cyanoacrylate adhesive (super glue). Here is how:

Materials needed:

  • Cyanoacrylate adhesive (super glue)
  • Toothpicks for application
  • Acetone nail polish remover
  • Soft polishing pad


  1. Ensure the crack is fully clean and dry.
  2. Use a toothpick to apply a small amount of cyanoacrylate glue deep into the crack.
  3. Press the crack edges together firmly for 30 seconds to bond.
  4. Remove any excess glue immediately with acetone on a cloth.
  5. Gently polish the countertop surface with the pad to blend.
  6. Leave the glue to cure for 24 hours before use.

The bonded cyanoacrylate adhesive will close the hairline crack while still retaining flexibility. With careful application, the repair can be almost invisible.

Repairing Medium Cracks

For slightly larger cracks up to 5mm wide, a clear epoxy adhesive works well. Here are the steps for this method:

Materials needed:

  • Two-part clear epoxy adhesive
  • Epoxy applicator gun
  • Plastic spreader or putty knife
  • Soft polishing pad
  • Masking tape


  1. Clean and dry the crack thoroughly.
  2. Apply masking tape along each side of the crack to protect the countertop.
  3. Load the two-part clear epoxy into the applicator gun.
  4. Fill the crack fully with epoxy adhesive, keeping it mounded above the surface.
  5. Use the spreader to smooth off the excess epoxy, feathering the edges.
  6. Remove the tape before the epoxy dries.
  7. After curing, gently polish the countertop to blend the epoxy.

The flexible epoxy sealant will bond securely inside the crack for a smooth, transparent repair.

Repairing Large Cracks

For cracks wider than 5mm, the best solution is to use color-matched quartz filler powder. Here is a step-by-step guide for this repair method:

Materials needed:

  • Color-matched quartz filler powder
  • Clear epoxy adhesive
  • Epoxy spreader or putty knife
  • Mixing stick or paddle
  • Soft polishing pad
  • Masking tape


  1. Clean and dry the crack thoroughly before starting.
  2. Prepare the filler by mixing quartz powder into clear epoxy resin.
  3. Apply masking tape along each side of the crack.
  4. Use the stick to fill the crack fully with the quartz-epoxy filler.
  5. Allow the filler to slightly harden for 10-15 minutes.
  6. Remove excess filler by scraping along the tape edges with a spreader.
  7. Once cured, gently polish the countertop surface to smooth and blend.
  8. Carefully remove the tape to reveal the repair.

Matching the filler color and texture prevents a visible patch. Allow a full 24 hours cure before using the countertop.

Reinforcing the Repaired Crack

To prevent cracks from recurring after repairs, it helps to reinforce the area underneath. Two good options are:

Fiberglass mesh tape:

  • Apply epoxy adhesive to the underside of the crack.
  • Press fiberglass mesh tape into the epoxy.
  • Coat over with more epoxy and allow to fully cure before use.

Bracket supports:

  • Mark the area to be supported underneath.
  • Adhere metal brackets onto the cabinet with epoxy.
  • Adjust brackets to snugly fit and support the countertop.

Reinforcements provide extra stability and prevent future cracking. Use them for repairs near cutouts or spanning gaps.

Preventing Quartz Countertop Cracks

While cracks can happen unexpectedly, you can take steps to prevent them occurring:

  • Avoid direct high heat on the countertop from hot pots and pans. Use trivets and mats.
  • Don’t apply very heavy loads that could cause impact damage.
  • Ensure cabinets and supports are level with no gaps to avoid flexing.
  • Clean spills immediately to prevent moisture seeping into cracks.
  • Use foam insulation under dishwashers and sinks to prevent vibration damage.
  • Avoid exposing the edges of an overhang to moisture or weather.

With proper care, your quartz countertops can remain crack-free for many years. But minor cracks can be repaired nearly invisibly when they do occur.

FAQs About Fixing Quartz Countertop Cracks

What are the best materials to repair a crack in a quartz countertop?

For hairline cracks, use cyanoacrylate (super glue). For small and medium cracks, a flexible clear epoxy works well. Wide cracks are best filled with quartz filler powder mixed into epoxy resin to match the color.

Should I use a stain to match the quartz color when repairing?

No, don’t use a stain. It will not bond well. It’s better to source quartz filler powder in the exact color match for the countertop. Mixing it with clear epoxy will provide results almost identical to the original quartz.

Is there an easy homemade fix using things like nail polish or wood glue?

Avoid DIY fixes like nail polish, wood glue, or acrylic caulk as they will not bond quartz securely or match the color and texture. Use the proper adhesives like cyanoacrylate glue and epoxy resin for professional quality results.

Can cracks reappear in a quartz countertop after repairing them?

It’s possible for cracks to return, especially if the cause of the original crack persists. Reinforce repairs with supports or fiberglass mesh tape underneath. Take care to prevent hot pots, excess loads, and vibration damage. Proper maintenance helps prevent recurring cracks.

Is it okay to use the countertop immediately after the repair?

Most adhesives require 24 hours of full curing time before the countertop can be used. Read product directions. Briefly test the bond by gently pressing on the repair before use. Avoid any heavy impact for a few days to allow the best bond.


Cracks in quartz countertops can happen but don’t have to be an eyesore or damaged permanently. With the right materials and techniques, you can often repair cracks to restore a near-flawless finish. Carefully assess the crack before choosing the best repair method. Keep the area clean, dry, and properly supported. Hairline cracks, small chips, and minor damage can often be fixed yourself, but larger cracks may benefit from a professional touch. With a quality quartz crack repair, your countertops can look pristine again.