265/40R18 tires
Prices, best picks and current deals for 265/40R18, a common size on performance cars. It fits the Porsche 911, Porsche Boxster/Cayman and more.
Yes, this fits your Porsche Boxster/Cayman. 265/40R18 is the original size on the rear axle on the 2005-2012 Porsche Boxster/Cayman.
The sticker inside the driver's door is still the final word, because trim and wheel package can change the size. Back to every Porsche Boxster/Cayman size.
What 265/40R18 tires cost
Nitto NT555 G2
Lowest price that still brakes and wears acceptably. Fine for a second car or low annual mileage.
Hankook Ventus S1 AS (H125)
The value sweet spot: long mileage warranty, solid wet grip, sane price.
Listed as Hankook Ventus S1 AS (H125) UHP All Season 265/40ZR18 101Y Passenger Tires
Continental ExtremeContact
The strongest wet and snow braking and the longest tread life among what is stocked in this size. Worth it if you keep the car.
Listed as Continental ExtremeContact 265/40ZR18 101Y Sport 02 Passenger Tires
Prices are per tire, before mounting and balancing. A set of four in the mid range comes to roughly $460 to $1,004, and a brand rebate can take another $50 to $110 off, see this month's deals.
Cheapest 265/40R18 right now
Aplus Shredder A/T 265/40R18 101H All Terrain Off-Road Light Truck Tires
$95.96per tire $191.92 for 2 tires (one axle)
14 tires in this size, priced straight from SimpleTire's own product feed, read 13 November 2026. Stock and prices move daily, so check the shop for today's figure.
See every 265/40R18 tire in stock at SimpleTire
About the 265/40R18 size
Classic Porsche rear size on 18 in wheels. Fit it as a matched pair with the 235/40R18 fronts - Porsche N-spec versions cost more but keep the handling balance the car was set up for.
What the numbers on the sidewall mean
A 265/40R18 tire is 265 millimeters wide, its sidewall is 40 percent of that (about 4.2 inches tall), and it mounts on a 18-inch wheel. That works out to an overall diameter of roughly 26.3 inches. Every replacement has to match all three numbers, and the load index and speed rating on the placard inside the driver's door have to be met or exceeded.
Our guide on reading a tire size walks through the markings, and this one lists every load index and speed code.
Our three picks, side by side
One tire at each price level from what the retailer stocks in this size, with the mileage warranty and UTQG grades as published by the manufacturers and their retailers. Treadwear is the number to compare: it is a relative wear rate, so 700 should last roughly twice as long as 350 on the same car.
| Nitto NT555 G2 | Hankook Ventus S1 AS (H125) | Continental ExtremeContact | |
|---|---|---|---|
| Price per tire (Nov 13, 2026) | not stocked today | $225.99 | $285.99 |
| Set of four | — | $903.96 | $1,143.96 |
| Service description in 265/40R18 | — | — | — |
| Mileage warranty | no mileage warranty; workmanship warranty, pro rata to 2/32" | see listing | see listing |
| UTQG treadwear / traction / temperature | 320 AA A (typical, varies by size) | see listing | see listing |
| Season | Ultra-high-performance summer | see listing | see listing |
| Extras | — | — | — |
What 265/40R18 tires cost across the whole range
Of the 22 tires listed in this size, 14 are in stock today. The lowest price is the Aplus Shredder A/T at $95.96, a 101H tire. The median is $204.99; a third of the tires cost $114.96 or less, and the top five percent start above $405.96. Those are per-tire prices before mounting and balancing, which adds $15 to $45 per tire at most shops, read from the retailer's feed Nov 13, 2026.
The same tires in neighboring sizes
The Hankook Ventus S1 AS (H125), our mid-range pick here at $225.99, is also stocked in 285/30R19 ($293.99), 245/40R20 ($255.99) and 275/35R20 ($271.99). The Continental ExtremeContact, our premium pick here at $285.99, is also stocked in 235/40R18 ($192.99), 235/40R19 ($241.99), 295/30R20 ($398.99) and 215/45R18 ($189.99). Useful if your vehicle came with a different wheel package, or if you are comparing an upsize: the same tire usually costs more per inch of wheel, not per inch of rubber. Prices per tire, from the retailer's feed Nov 13, 2026.
Winter and this size: summer tires are not winter tires
Many tires sold in this size are summer tires, and the manufacturers advise against driving them in near-freezing temperatures: the compound hardens, grip drops sharply and the tread can crack. They also carry no M+S or 3PMSF marking, so a car on summer tires fails Colorado's Passenger Vehicle Traction Law outright on the 126 miles of I-70 between Dotsero and Morrison, in force from September 1 to May 31, unless it is all-wheel drive with at least 3/16 inch of tread; fines start at $130. If the car is driven year-round in a state with real winters, either run an all-season or all-weather tire in this size or keep a second set of winter tires, often on a smaller, narrower wheel that is also less expensive.
None of our picks in this size, the Nitto NT555 G2, carries the 3PMSF symbol; for that, look at the all-weather and winter tires.
Vehicles that use 265/40R18
- Porsche 911 (2005-2011, 997 rear)
- Porsche Boxster/Cayman (2005-2012, 987 18 in rear)
Other years and wheel packages of the same models came on 245/35R20, 235/40R18 or 235/40R19 instead, so read the placard inside the driver's door before you order.
Which type of 265/40R18 tire?
All-Season Tires
Drivers in the South, West Coast and mild parts of the Midwest who want one set of tires that lasts a long time and is quiet.
Summer Tires
Sports-car and performance-sedan owners, and anyone in a warm climate who wants the best possible grip and steering.
Performance Tires
Owners of sports sedans, hot hatches and performance crossovers who want year-round tires with real handling.
Frequently asked questions
How much do 265/40R18 tires cost?
Expect $96–$115 per tire for a budget brand, $115–$251 for a mid-range tire like the Hankook Ventus S1 AS (H125), and $251–$406 for a premium tire like the Continental ExtremeContact. A set of four therefore starts at about $384. Add roughly $15 to $45 per tire for mounting and balancing.
What vehicles use 265/40R18 tires?
265/40R18 is original equipment on Porsche 911 (2005-2011, 997 rear) and Porsche Boxster/Cayman (2005-2012, 987 18 in rear), among others. Always confirm with the sticker inside your driver's door, because trim levels and wheel packages can change the size.
What is the best 265/40R18 tire?
For most drivers our mid-range pick, the Hankook Ventus S1 AS (H125), is the sweet spot of price and tread life. If you keep the vehicle a long time or drive in heavy rain and snow, the Continental ExtremeContact is worth the extra. On a tight budget the Nitto NT555 G2 is a sound choice.
Can I replace just one or two 265/40R18 tires?
On a front- or rear-wheel-drive car, yes: replace in pairs on the same axle and put the newer pair on the rear. On all-wheel-drive vehicles most makers want all four replaced together, or a new tire shaved to match, because a difference in circumference strains the drivetrain.