295 is the tyre width in millimetres, 40 is the profile (sidewall height as a percentage of width), and R21 is a 21-inch rim diameter. To confirm fitment, match the size to your door-jamb sticker or handbook and check the full spec on your current tyres, including load index and speed rating. Also confirm your wheel width is compatible with this size (many 295/40 R21 options suit wider rims, but exact approval varies by tyre model).
Many vehicles that use 295/40 R21 require an XL (Extra Load) construction because of higher axle weights and loads. Check your vehicle placard or handbook for the minimum load index, then choose a tyre that meets or exceeds it. If XL is specified, avoid switching to a standard load version, as it can reduce load capacity and may not be road legal for your vehicle.
Choose a speed rating that meets or exceeds the rating listed on your vehicle placard or your current tyres, as this is tied to the vehicle’s type approval. This size is commonly available in higher ratings (often W or Y), but the correct choice depends on the exact model and trim. If selecting winter tyres with a lower speed rating, follow UK guidance for a visible speed reminder and do not drive beyond that rating.
It is often fitted as a rear size on performance SUV wheel packages, paired with a narrower front tyre for steering feel and traction balance. If your vehicle is staggered, you cannot rotate front to rear, so maintaining even wear through correct pressures and alignment becomes more important. When replacing, fit the same model and similar tread depth across the same axle to keep handling consistent.
Runflat versions are available in many 295/40 R21 ranges, but whether you should use them depends on your vehicle’s original specification and puncture support (spare wheel, space saver, or sealant kit). If your car was supplied with runflats, switching to non-runflats can change ride and steering feel, and you should confirm the manufacturer allows it. Avoid mixing runflat and non-runflat tyres on the same axle.
