Winter 205/40r18s? Or just swap the wheels for winter?
 

Have a bit of a conundrum on my hands:

Bought a ‘23 Cooper S with the 18” Union Jack wheels. Love them, but the tires that came with are runflat (which I appreciate and would like to keep, as this car has no doughnut spare).

The problem: I live in VT and you can’t get by without Winter-specific tires after late October. Runflats are expensive and this size/type isn’t manufactured by my go-to (Nokian Nordmans are my usual, and I love ‘em).

The question: Should I just buy the Runflats recommended by the dealership (but obv not through them), OR investigate switching for the winter? There’s not a whole lot of clearance between my tire and the wheel well, so a standard tire might not even fit. Can I reduce the wheel size and just get a smaller set of rims for winter?

thanks in advance.

I would heartily recommend getting a second set of wheels and tires for winter use. Being a Cooper S, you could probably go down to 16" wheels for winter. Tires will be MUCH less expensive in that size.

I second the opinion for a second set of winter wheels. A no brainer for Vermont, for sure!

Another vote for 2nd set of wheels for winter.
My R50 Cooper in Minnesota has a second set of matching white "holies" with mounted Blizzak WS-60's
Sure makes all the difference when the big flakes fly!

The OP has a 2023 Cooper S with front brake calipers too large to fit small diameter MINI wheels like those that fit a 2005 R 50 base Cooper.

However the theory is sound and will work provided you get the right wheels. Checking with tirerack.com for a new Cooper S that comes with 18" wheels it seems they offer-

17x7" et 35 Borbet Type F wheels in black and silver painted
This will fit 205/45-17 tires which for snow could include:

Vredestein Wintrac Pro $157 each
Tirerack test result:
https://www.tirerack.com/tires/tests...y.jsp?ttid=284
Pirelli Winter Sottozero 3 $161 each
Tirerack test result:
https://www.tirerack.com/tires/tests...y.jsp?ttid=181
Yokohama Bluearth Winter V905 $156 each

If you have an "S" hardtop, can't you fit 16" wheels. Aren't there good winter tires in 195/55 x16?

OK, so the first search I did on tirerack.com was for a 2023 MINI JCW and the results above were all that were offered.

Then I searched for 2023 MINI Cooper S and I now got:
12 wheels in 16x6.5 et 43-54 range

Tiresizes
185/55-16 (tire diam. 24")
Michelin X-Ice Snow tire $165 each, Perfect fit for 6" wide rim but will fit up to 6.5" wide rim OK. 87 load rated
195/55-16
Blizzak WS90 (Studless ice and snow tire) $156 each
Tirerack test result- https://www.tirerack.com/tires/tests...y.jsp?ttid=263
205/50-16
205/55-16 (tire diam. 24.8")
Michelin X-Ice Snow tire $165 each, perfect fit for 6.5" wide rim, 94 XL load rated
225/50-16

These are all possible. More narrow tire sizes may handle more snow depth.