On 4x4 and SUV tyres, the markings H/T, A/T and M/T describe the tread type, how road-biased or off-road-focused a tyre is. They are not sizes or load ratings; they tell a buyer what the tyre is built to do.
The three tread types
| Marking | Tread type | Built for |
|---|---|---|
| H/T | Highway Terrain | On-road comfort and quietness |
| A/T | All-Terrain | A balance of road and off-road |
| M/T | Mud-Terrain | Serious off-road and mud |
Highway-terrain (H/T)
Highway-terrain tyres are the most road-biased. Their tread is closer to a car tyre's, giving a quiet, comfortable and long-wearing tyre suited to SUVs that spend nearly all their time on tarmac. They offer the least off-road grip of the three, which for most road-going SUVs is no drawback at all.
All-terrain (A/T)
All-terrain tyres are the all-rounder, and the most popular choice for 4x4s that see a mix of surfaces. A chunkier, more open tread gives genuine capability on gravel, grass and light mud, while keeping reasonable road manners. They are a little noisier and slightly less refined than highway tyres, but for vehicles that occasionally leave the road they strike a sensible balance.
Mud-terrain (M/T)
Mud-terrain tyres have an aggressive, blocky tread with large gaps designed to bite into mud and rough ground and clear themselves as they turn. They are the choice for serious, frequent off-road use, and are often fitted in the larger flotation sizes. The trade-off is felt on the road: they are noticeably noisier, less comfortable and wear faster on tarmac than the other two. For a vehicle that rarely goes off-road, they are more tyre than the job needs.
Choosing, and a note on winter
The right type follows the mix of driving: mostly-road vehicles suit highway or all-terrain tyres, while mud-terrain earns its place only with regular off-road use. The choice sits alongside getting the correct size and rating for the 4x4.
One winter point is worth knowing. Many all-terrain tyres carry the M+S marking, and some also carry the three-peak snowflake symbol that certifies real severe-snow performance. For a 4x4 that needs to cope with winter, looking for the snowflake is the way to tell which all-terrain tyres are genuinely up to it. Reputable tyre retailers such as Tyres.co.uk let you filter by size, which narrows the all-terrain choice down to the ones in the right fitment for the vehicle.
From the workshop: the mud-terrain look is popular, but a lot of drivers who ask for them spend ninety percent of their time on the road, where they are loud and wear quickly. Unless someone is genuinely off-road often, all-terrain is usually the tyre that serves them best.
Common questions
What do H/T, A/T and M/T mean on a 4x4 tyre?+
They mark the tread type. H/T is highway-terrain, road-biased and comfortable. A/T is all-terrain, a balance of road and off-road. M/T is mud-terrain, an aggressive tread for serious off-road use. They describe what the tyre is for, not its size.
What is the difference between all-terrain and mud-terrain tyres?+
All-terrain (A/T) tyres balance on-road manners with off-road capability and suit most mixed use. Mud-terrain (M/T) tyres have a much more aggressive, blocky tread for serious mud and rough ground, but are noisier, less refined and wear faster on tarmac.
Which 4x4 tyre type should I choose?+
It depends on the mix of driving. Mostly-road SUVs suit highway or all-terrain tyres, all-terrain being the popular all-rounder. Choose mud-terrain only for genuine, frequent off-road use, as the trade-off on the road is noise, comfort and tyre life.
Are all-terrain tyres good in winter?+
Some are. Many all-terrain tyres carry the M+S marking, and some also carry the three-peak snowflake symbol that certifies real severe-snow performance. Checking for the snowflake is the way to tell which are genuinely winter-capable.