What size tires does the Cadillac Optiq take?

It runs 245/50 R20 and 275/40 R21. The exact fitment for your car is on On the driver's door jamb, on the B-pillar.

Can I fit a cheaper tire to a Cadillac Optiq?

Only at 245/50 R20 105H XL or better. That is the figure to hold: a tire below the load index, the speed rating or the construction class is not a cheaper one, it is the wrong one.

Cadillac Optiq tires

The Cadillac Optiq leaves the factory on 245/50 R20 and 275/40 R21 depending on wheel size, and the 245/50 R20 105H XL below is the one most owners are replacing. XL is not optional here; it is what the car was type approved on. The Jaguar I-Pace takes the same size.

Every fitment

Generation	Trim	Wheel	Tire size	Load index	Speed	Construction	Marking	Pressure
Current	Luxury and Sport (20in)	20in	245/50 R20	105	H	XL	none	see plate
Current	Luxury, Sport and V (21in)	21in	275/40 R21	107	H	XL	none	see plate

What you are looking for, drawn. The real one is on on the driver's door jamb, on the b-pillar, and its figures are the ones that count.

Your own placard is the authority. You will find it on the on the driver's door jamb, on the B-pillar. Where it disagrees with this page, it wins. Match or exceed the size, load index, speed rating and construction class it gives, and use its pressure figure rather than anything printed on the tire.

What changes on this car

Both Optiq fitments are XL, including the 20 inch 245/50 R20 105H. In that size a standard-load tire stops short of 105.

The 21 inch 275/40 R21 107H XL is the same size and index as the Equinox EV's 21 inch wheel. The two share GM's compact Ultium base.

Michelin lists the Optiq-V only on the 21 inch, at the same H rating as the other trims.

The placard gives 42 psi on every corner for both sizes.

No tires listed against this fitment yet. Product specifications are published from each manufacturer's own data and that work is not finished for 245/50 R20. Match or exceed every figure in the table above and you cannot go far wrong.

Where these figures come from

Michelin US vehicle fitment tool (2025 Luxury 1, 245/50R20/XL 105H): https://www.michelinman.com/auto/browse-tires/by-vehicle/2025/cadillac/optiq/luxury-1/245---50R20---XL-105H checked October 5, 2026
Michelin US vehicle fitment tool (2026 Sport, 245/50R20/XL 105H): https://www.michelinman.com/auto/browse-tires/by-vehicle/2026/cadillac/optiq/sport/245---50R20---XL-105H checked October 5, 2026
Michelin US vehicle fitment tool (2025 Sport 2, 275/40R21/XL 107H): https://www.michelinman.com/auto/browse-tires/by-vehicle/2025/cadillac/optiq/sport-2/275---40R21---XL-107H checked October 5, 2026
Michelin US vehicle fitment tool (2026 V, 275/40R21/XL 107H): https://www.michelinman.com/auto/browse-tires/by-vehicle/2026/cadillac/optiq/v/275---40R21---XL-107H checked October 5, 2026
BFGoodrich US vehicle fitment tool (2025 Luxury 2, 245/50R20/XL 105H): https://www.bfgoodrichtires.com/auto/browse-tires/by-vehicle/2025/cadillac/optiq/luxury-2/245---50R20---XL-105H checked October 5, 2026

Every figure here comes from one tire maker's own fitment data, checked across different years or trims. That is a second look rather than a second opinion, so check the label on your door jamb before you buy.

Spotted something wrong? A correction to a fitment is the most useful thing you can send us and it goes to the front of the queue. Tell us.

Fit tires for a living? Dealer accounts get volume pricing on every tire we list. Open an account.

Other cars on the same size

Common questions

What size tires does the Cadillac Optiq take?: It runs 245/50 R20 and 275/40 R21. The exact fitment for your car is on On the driver's door jamb, on the B-pillar.
Can I fit a cheaper tire to a Cadillac Optiq?: Only at 245/50 R20 105H XL or better. That is the figure to hold: a tire below the load index, the speed rating or the construction class is not a cheaper one, it is the wrong one.