What is the minimum tyre tread depth for the Irish driving test?
Direct Answer
The legal minimum tyre tread depth in Ireland is 1.6 millimetres across the central three-quarters of the tyre tread around the entire circumference. If tyre tread is below 1.6mm or tyres are damaged, the examiner will cancel the test immediately.
Key Takeaways at a Glance
- ✓Legal requirement: Minimum 1.6mm across central 3/4 of tyre tread.
- ✓Check Tread Wear Indicators (TWIs) located in the main tyre grooves.
- ✓Tyres must be free from bulges, deep cuts, tears, or exposed cords.
- ✓Test will be aborted immediately if tyres fail inspection; fee is forfeited.
Detailed Legal & Test Explanation
Roadworthiness of your vehicle is a strict prerequisite for sitting the practical driving test. Examiners conduct a physical inspection of all four road tyres before beginning the road portion of the examination.
The legal minimum tyre tread depth for cars in Ireland is 1.6mm across the middle 75% (central three-quarters) of the tyre width and around the entire outer circumference. Most tyres feature Tread Wear Indicators (TWIs)—small raised bars within the main tread grooves—that sit at exactly 1.6mm.
In addition to tread depth, examiners inspect tyres for severe defects such as visible bulges, cuts longer than 25mm, ply or cord exposure, or severely mismatched tyre sizes. If any tyre is deemed non-compliant or defective, the examiner is required by RSA protocol to abort the test. Your test fee is forfeited, and you must rebook and pay again.
Examiner Watchout & Common Pitfall
Examiners regularly ask pre-test technical questions such as: 'How would you check the tyre tread depth and condition?' The model answer is to check the tread depth using a depth gauge or looking for the tread wear indicators (1.6mm), and check the tyre walls for bulges, cracks, and pressure.
Related Test Prep Resources
Know the route before test day.
Turn nervous drives into focused practice. Follow independent route patterns with clear, turn-by-turn voice guidance on iPhone and Android.
Built for iPhone & Android
Practise at your own pace