The 2020 Lexus IS300 sits in the modern sport-sedan tradition, blending compact luxury proportions with the crisp, road-focused stance buyers expect from the IS line. Tire fitment matters here because this chassis can appear with either a square 225/45R17 setup or a staggered 18-inch arrangement using 225/40R18 in front and 255/35R18 in back. All three primary sizes are radial fitments, so the main decision is not vintage construction versus modern construction, but choosing the correct wheel diameter and layout first. From blackwall performance options to raised white letter and redline treatments in 17-inch form, the right selection depends on how the car is equipped and how closely you want to balance appearance, handling character, and fitment accuracy.
Which Tire Size Is Right for The 2020 Lexus IS300
The 2020 Lexus IS300 uses three primary tire sizes across two wheel diameters, and the correct choice depends first on whether the car has the 17-inch setup or the staggered 18-inch front-and-rear arrangement. Before selecting a tire, confirm the exact sub-model position and wheel size, because the 18-inch fitment uses different sizes at the front and rear rather than one universal size.
225/45R17 is a modern metric radial size in which 225 identifies the nominal section width in millimeters, 45 is the aspect ratio, R indicates radial construction, and 17 is the wheel diameter in inches. On the 2020 Lexus IS300, this size suits the 17-inch square setup rather than the staggered 18-inch package. Available choices include BFGoodrich, Nitto, and Pro-Trac products, with blackwall, raised white letter, and redline sidewall treatments. This size is the right starting point when the car carries 17-inch wheels and you want to compare tire series, appearance, and rim-width compatibility within that configuration.
Fit(s): (AWD) Front, (RWD) Front, F Sport Black Line Special Edition Front, and F Sport Front
Construction: Radial|Rim: 18 in
225/40R18 is a modern metric radial size with a 225-millimeter nominal section width, a 40-series profile, radial construction, and an 18-inch rim diameter. On the 2020 Lexus IS300, this is a front-position size used on the staggered 18-inch setup rather than a four-corner fitment for every configuration. Product choices center on blackwall performance-oriented offerings from BFGoodrich and Nitto across several g-Force, Phenom, and NT555 G2 series options. This size should be evaluated only after confirming that the car uses the 18-inch front fitment and has not been changed to a different wheel package.
Fit(s): (AWD) Rear, (RWD) Rear, F Sport Black Line Special Edition Rear, and F Sport Rear
Construction: Radial|Rim: 18 in
255/35R18 is a modern metric radial size where 255 denotes the nominal section width in millimeters, 35 is the aspect ratio, R marks radial construction, and 18 identifies the wheel diameter. For the 2020 Lexus IS300, this size serves the rear position on staggered 18-inch applications and is paired with a narrower 225/40R18 front tire. Available products come from BFGoodrich and Nitto in blackwall form, with differences in tire series, rim-width recommendations, and other specifications. This is the rear fitment to check when maintaining the intended staggered layout rather than converting the car to a same-size arrangement.
Tire fitment on the 2020 Lexus IS300 is split between a 17-inch square setup and a staggered 18-inch setup, so confirming the exact sub-model and wheel position matters. Some versions use the same size at all four corners, while others use one size in front and a wider size in back.
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2020 Lexus IS300 (AWD)
The 2020 Lexus IS300 (AWD) uses the 225/45R17 radial fitment on a 17-inch wheel. Tire selection here is mainly about choosing among available brands, series, and sidewall styles rather than sorting through front-to-rear staggered sizing.
The 2020 Lexus IS300 (AWD) Front uses 225/40R18 as the front half of the staggered 18-inch setup. That means the front tires should be chosen with the matching rear size and the actual wheel package in mind, not as a stand-alone four-corner fitment.
The 2020 Lexus IS300 (AWD) Rear uses 255/35R18 as the wider rear tire in the staggered 18-inch arrangement. This rear fitment should be matched to the corresponding 225/40R18 front size and checked against the wheels currently on the car.
The 2020 Lexus IS300 (RWD) also uses the 225/45R17 radial size on its 17-inch configuration. Buyers with this setup can focus on brand, series, and sidewall presentation without dealing with the extra complexity of a staggered front-and-rear combination.
The 2020 Lexus IS300 (RWD) Front uses 225/40R18 on the front axle when equipped with the staggered 18-inch arrangement. Tire selection should account for the matching rear size and for keeping the intended front-to-rear relationship intact.
The 2020 Lexus IS300 (RWD) Rear uses 255/35R18 as the rear tire on the staggered 18-inch setup. Choosing this size correctly means confirming the rear wheel width and preserving compatibility with the front 225/40R18 fitment.
2020 Lexus IS300 F Sport Black Line Special Edition Front
The 2020 Lexus IS300 F Sport Black Line Special Edition Front uses 225/40R18 as its front fitment. This places the tire decision around the 18-inch staggered package, so front-tire choice should be considered alongside the rear size and the car's existing wheel setup.
2020 Lexus IS300 F Sport Black Line Special Edition Rear
The 2020 Lexus IS300 F Sport Black Line Special Edition Rear uses 255/35R18 at the rear. That wider rear sizing is part of the staggered 18-inch arrangement, making wheel confirmation and proper front-and-rear pairing more important than appearance alone.
The 2020 Lexus IS300 F Sport Front uses 225/40R18 as the front tire size. Because it belongs to a staggered setup, the front tire should be selected with attention to the corresponding rear fitment and the actual 18-inch wheels on the car.
The 2020 Lexus IS300 F Sport Rear uses 255/35R18 as its rear tire size. That makes this a rear-specific fitment decision, with emphasis on maintaining the staggered arrangement and confirming rear wheel compatibility before changing series or brand.
The tire sizes listed on this page assume factory-standard vehicle configuration. The following modifications may affect tire fitment and are not reflected in this guide:
Suspension changes (lowering, lift kits, spring replacements)
Body alterations (fender modifications, custom bodywork)
If your vehicle has been modified from factory specifications, verify tire clearance before purchase.
Best 2020 Lexus IS300 Tires for Sale
Available 2020 Lexus IS300 tires center on 225/45R17, 225/40R18, and 255/35R18 radial sizes from BFGoodrich, Nitto, and Pro-Trac. Depending on size, buyers can compare blackwall performance series, plus raised white letter and redline styling in selected 17-inch options.
The most common 2020 Lexus IS300 tire questions involve identifying the correct size by wheel package, understanding the staggered 18-inch setup, and comparing available brands, sidewall styles, and product series before the car goes back on the road.
Tire Size & Fitment
What tire size fits a 2020 Lexus IS300?
The 2020 Lexus IS300 uses three primary tire sizes: 225/45R17, 225/40R18, and 255/35R18. The 17-inch setup uses 225/45R17, while the 18-inch arrangement is staggered, with 225/40R18 in front and 255/35R18 in back.
The key step is confirming which wheel package is actually on the car before ordering tires. A 17-inch square setup and an 18-inch staggered setup are not selected the same way, and a front 18-inch size should not be treated as a universal four-corner fitment without checking the vehicle's current configuration.
What size rim does a 2020 Lexus IS300 use?
The 2020 Lexus IS300 uses either a 17-inch or 18-inch rim, depending on configuration. The 225/45R17 fitment belongs to the 17-inch setup, while the 225/40R18 front and 255/35R18 rear sizes are used with 18-inch wheels.
Wheel diameter should be verified directly on the car because it determines which tire size family even belongs in the discussion. On 18-inch applications, position matters too, since the front and rear sizes are different, and aftermarket wheel changes can complicate a size choice that looks simple at first glance.
Why does the 2020 Lexus IS300 have more than one tire size?
More than one tire size appears on the 2020 Lexus IS300 because the model can be equipped with either a 17-inch square arrangement or a staggered 18-inch setup. In staggered form, the car uses 225/40R18 in front and 255/35R18 in the rear rather than the same size at all four corners.
That means tire selection starts with the actual wheel package and axle position, not just the year and model name. Checking the wheels already on the car helps prevent mixing a square-fitment size with a staggered package, especially if the car has seen wheel, suspension, or trim-package changes over time.
Choosing the Right Tire
What should I consider when choosing a tire for a 2020 Lexus IS300?
Start with the correct size and wheel layout for the car: 225/45R17 for the 17-inch setup, or the staggered 18-inch pairing of 225/40R18 front and 255/35R18 rear. From there, compare radial tire series, sidewall style where available, and wheel-width compatibility within the correct size.
A buyer with 17-inch wheels may also weigh appearance more heavily because that size includes blackwall, raised white letter, and redline choices. On 18-inch applications, the decision is more focused on maintaining the intended front-and-rear fitment, checking wheel specifications, and selecting a tire series that suits how the car will actually be driven.
What sidewall styles are available for 2020 Lexus IS300 tires?
Sidewall style depends on tire size. In 225/45R17, available sidewall treatments include blackwall, raised white letter, and redline, while the 225/40R18 and 255/35R18 fitments are represented here in blackwall form.
That makes the 17-inch setup the more appearance-driven choice if a buyer wants something other than a plain blackwall look. Sidewall styling should still be chosen only after confirming the correct size and wheel diameter, since appearance options do not override the need to match the car's actual fitment.
What brands offer tires for the 2020 Lexus IS300?
Tires for the 2020 Lexus IS300 are available here from BFGoodrich, Nitto, and Pro-Trac. BFGoodrich and Nitto appear across the 17-inch and 18-inch metric radial sizes, while Pro-Trac appears in the 225/45R17 size with distinct sidewall styling options.
Brand choice is only one part of the decision. It helps to compare the exact tire series, the available sidewall presentation in the correct size, and the wheel-width range for the wheels currently on the car so the final selection matches both the vehicle setup and the intended look.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 2020 Lexus IS300?
Yes, modifications can affect tire fitment on a 2020 Lexus IS300 even when the tire size sounds correct on paper. Aftermarket wheels, changes in wheel width or offset, suspension lowering, and body-clearance differences can all influence how a 225/45R17, 225/40R18, or 255/35R18 tire sits on the car.
A practical check includes verifying wheel diameter, wheel width, and whether the car still uses its original square or staggered layout. Steering clearance in front and fender or suspension clearance at both ends are worth confirming before replacing only one pair, especially on cars that may have been personalized after leaving the showroom.
What should I inspect before driving a 2020 Lexus IS300 on new tires?
Before driving a 2020 Lexus IS300 on new tires, inspect the wheel size, confirm the front and rear tires match the intended configuration, and check that inflation is set correctly for the application. It is also smart to look over the wheels for damage and make sure valve stems and balancing hardware are in sound condition.
A short follow-up inspection after the first miles can catch issues such as vibration, air loss, or unexpected rubbing. Cars with staggered 18-inch tires deserve extra attention because front and rear sizes are different, so a quick visual check helps confirm the correct tires were mounted in the correct positions.
What should I check before a longer drive in a 2020 Lexus IS300?
Before a longer drive, check air pressure, tread condition, and the sidewalls for cuts, bulges, or cracking. On a 2020 Lexus IS300, it also helps to confirm that the car still wears the proper square 17-inch or staggered 18-inch tire arrangement and that there is no unusual wear pattern developing.
Road-trip preparation should include a quick look at wheel condition and any signs of vibration or pulling during the first miles. Uneven wear can point to alignment or suspension issues, and catching that early matters more on staggered applications because front and rear tires are not interchangeable in the same way as a square setup.
