What is the DOT code on a tyre?

The DOT code shows where and when the tyre was made. The last four digits are the week and year — for example 2723 means the 27th week of 2023.

What does M+S mean on a tyre?

M+S means mud and snow. It's a self-declared marking. For real winter performance, look for the 3PMSF (three peak mountain snowflake) symbol.

What does XL or HL mean?

XL means extra load — a reinforced tyre with a higher load capacity. HL is a newer marking for very high load tyres, often fitted to EVs and SUVs.

Where is the tread wear indicator?

Tread wear indicators (TWIs) are small raised bars in the main tread grooves. When the tread wears down level with the bars, the tyre is at 1.6mm — the UK legal minimum.

UK tyre basics

How to Read a Tyre Sidewall

Decode every marking on a UK tyre sidewall — size, load, speed, age, type and special markings.

Tyre Size Checker

Enter a UK tyre size such as 205/55 R16 91V to decode the width, profile, rim, load index and speed rating.

Tyre size

Find your tyre size on the sidewall, the driver's door frame, fuel flap or vehicle handbook.

Markings you'll see on a UK tyre

205/55 R16 91V — width, profile, construction, rim, load index, speed rating
XL or HL — extra load reinforced construction
RFT, RSC, ROF, SSR, DSST — run-flat technology
EV, HL, silent foam — EV-specific or noise-reducing tyres
M+S — mud and snow (self-declared)
3PMSF — three peak mountain snowflake (true winter performance)
DOT 2723 — week 27, year 2023 manufacture
TWI — tread wear indicator at 1.6mm
C, CP — commercial and motorhome ratings

What to check before fitting

Confirm the size matches your existing tyre or door frame sticker.
Check the load index meets or exceeds the original.
Check the speed rating meets or exceeds the original.
If your vehicle uses run-flat or EV-specific tyres, match the type.
Look for a DOT date code under 2-3 years old at point of fitting.
Check the EU label for wet grip, fuel efficiency and noise.

Frequently asked questions

Quick answers about UK tyre fitment, MOT rules and seasonal options.

What is the DOT code on a tyre?
The DOT code shows where and when the tyre was made. The last four digits are the week and year — for example 2723 means the 27th week of 2023.
What does M+S mean on a tyre?
M+S means mud and snow. It's a self-declared marking. For real winter performance, look for the 3PMSF (three peak mountain snowflake) symbol.
What does XL or HL mean?
XL means extra load — a reinforced tyre with a higher load capacity. HL is a newer marking for very high load tyres, often fitted to EVs and SUVs.
Where is the tread wear indicator?
Tread wear indicators (TWIs) are small raised bars in the main tread grooves. When the tread wears down level with the bars, the tyre is at 1.6mm — the UK legal minimum.

Tyre Finder UK provides general tyre guidance only. We do not guarantee tyre fitment, local stock, prices or fitting availability. Always confirm your tyre size, load rating, speed rating and vehicle requirements using your current tyre sidewall, vehicle handbook, manufacturer guidance or a qualified tyre fitter before fitting.