I've searched but can't seem to find the answer. Does anyone know what the wheel bolt pattern is or will be on the new 2021 IS300?

 

Welcome to the forum!

If you're looking for info on the 2021 model, so far, this is a great thread to check out: https://www.clublexus.com/forums/is-...hreads-67.html

To answer you question, the 2021 will still be a 5x114.3 bolt pattern with 60.1mm bore.
The only difference is Lexus has switched it to lug bolts as opposed to the previous stud and nut.

 

Great!! So the older rims will still fit fine then

 

Had some guys try using the 18" F sport accessory wheels and said that it wouldn't work due to the bolts being too short

 

So the wheels do fit, just need to get longer bolts.
I'm not sure how that translates into not working.
Its not uncommon with German vehicles to need different length bolts when installing wheels that are not the oem ones...or when installing spacers.

 

They've already received their 21 IS? I didn't think they would be delivered for about another week?

 

I'm sure the aftermarket will make long/extended bolts soon. In my BMW days, I always ran extended bolts w/ spacers. All the aftermarket companies sell them. In fact, if they're the same bolts as on the Supra (why not? Would save Toyota money) then they're the same bolts used on every BMW since the 80s. In that case, the bolts already exist in the aftermarket. Don't know for sure though so check it out.

 

They are in. We just looked at first one dealer got in Fife WA last Friday. It was sold before they even got it in. Ordered ours, hits port on 12th, dealer will have right before Thanksgiving.