20mm and 30mm are the two standard quartz worktop thicknesses. 30mm has a more substantial, traditional look and is usually the pricier option; 20mm is lighter, often more cost-effective, and can be mitred at the edge to look as thick as 30mm or 40mm if you want a chunkier appearance without the full material cost.
The straightforward differences
| 20mm | 30mm | |
|---|---|---|
| Appearance | Slimmer, more contemporary edge | Substantial, traditional edge |
| Weight | Lighter | Heavier, may need stronger cabinet support |
| Cost | Often more economical | Usually more expensive |
| Can be mitred to look thicker? | Yes | Not usually necessary |
| Durability | Excellent: same material properties as 30mm | Excellent: same material properties as 20mm |
Does thickness affect durability?
No, the material properties (hardness, non-porosity, scratch and stain resistance) are identical whichever thickness you choose. Thickness is primarily a design and structural decision, not a durability one.
What is a mitred edge?
A mitred edge is where two pieces of quartz are joined at a 45-degree angle along the front edge of the worktop, effectively doubling the visible edge thickness. It’s a popular way to get the look of a substantial 40mm or 60mm edge using 20mm material, giving you a chunky, premium appearance without the weight or cost of a full-thickness slab throughout.
Which should you choose?
- Choose 20mm if you want a slimmer, more contemporary look, want to manage cost, or want a mitred edge for a customisable thickness at the front only.
- Choose 30mm if you want a traditional, substantial worktop edge throughout, and aren’t concerned about the additional weight or cost.
A note on weight and cabinet support
30mm slabs are heavier than 20mm, which can matter for very long unsupported runs or large islands. Your fabricator will advise if additional cabinet bracing or support is needed for your specific layout, regardless of thickness chosen.
Frequently asked questions
Is 30mm quartz better than 20mm?
Not in terms of durability: both perform identically day to day. 30mm simply has a different, more substantial appearance and is generally the pricier option.
Can 20mm quartz look like 30mm?
Yes, a mitred edge doubles the visible thickness at the front edge, giving 20mm material the appearance of a much thicker slab without the added weight or cost throughout.
Which thickness is more common in UK kitchens?
Both are widely used; 20mm has become increasingly popular for its lighter, more contemporary look, especially with a mitred edge, while 30mm remains popular for a traditional, substantial appearance.
Explore more
Browse the full range of 47 designs, see our guide to quartz worktop costs, or read about edge profiles. Get a quote for your project.