How to Check Your Tyre Tread Depth — and Why It Matters
HomeArticlesHow to Check Your Tyre Tread Depth — and Why It Matters
Safety Tips
25 February 2026
3 min read
Fred's Towing Team

How to Check Your Tyre Tread Depth — and Why It Matters

Driving on worn tyres is illegal, dangerous, and one of the leading causes of blowouts and loss of control. Here's how to check yours in under two minutes.

Tyre tread depth is one of the most important — and most overlooked — safety checks a driver can make. Here's the fast guide.

The Legal Minimum

In the UK, the legal minimum tread depth for cars is 1.6mm across the central three-quarters of the tyre width, around the full circumference. Driving below this limit carries a fine of up to £2,500 per tyre and 3 penalty points.

The 20p Test

No tread gauge? Use a 20p coin. Insert it into the main tread grooves. If the outer band of the coin is visible, your tread is below 3mm — consider replacing soon. If the band disappears into the groove, you're above 3mm.

Why 3mm Is the Real Threshold

While 1.6mm is the legal limit, stopping distances increase dramatically below 3mm — especially in wet conditions. Most tyre safety organisations recommend replacing at 3mm, not waiting until 1.6mm.

Checking the Whole Tyre

Don't just check one spot. Tyres wear unevenly:

  • Centre wear — over-inflation
  • Edge wear — under-inflation
  • One-sided wear — alignment or suspension issue
  • Uneven wear patterns mean something else needs fixing too.

    Tyre Age

    Even with good tread, tyres degrade with age. Most manufacturers recommend replacing tyres over 6 years old regardless of tread depth — check the 4-digit date code moulded into the sidewall (e.g. 1423 = 14th week of 2023).


    Suffered a tyre blowout? Fred's Towing Services provides roadside assistance and recovery across Newport, Cardiff, Bristol and Bath. Call 01633 982028.

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