285 is the tyre width in millimetres, 50 is the sidewall height as a percentage of that width, R means radial construction, and 18 is the wheel diameter in inches. Matching these numbers exactly ensures the tyre seats correctly on the rim and keeps the intended rolling diameter for your vehicle.
The 18 confirms the correct rim diameter, but rim width also matters with a 285 mm tyre. Most manufacturers approve a rim width range for 285/50 R18 (often around 8 to 10 inches, depending on the model), so check the wheel width stamped on the rim or in your handbook and compare it with the tyre specification before ordering.
Choose a load index and speed rating that meet or exceed the minimum shown on your vehicle tyre placard or handbook. Many 285/50 R18 options are offered with higher load ratings suited to larger SUVs, but the correct requirement varies by model and whether it is a front, rear, or all-round fitment.
Pick XL only if your vehicle placard specifies it, or if you need the tyre to meet a higher load requirement for your exact fitment. XL can be a good match for heavier SUVs or regular towing when it is approved for the vehicle, but the priority is always meeting the stated load rating and using the correct tyre pressures.
Summer tyres suit mainly mild UK conditions and offer strong dry and wet-road performance in warmer temperatures. Winter tyres are the best choice for frequent cold weather, ice and snow, while all-season tyres are a practical year-round option and are worth prioritising with a 3PMSF marking if you want broader cold-weather capability without changing sets.
