This is a normal thing that people do. They buy steel wheels and attach winter tires to them, for many obvious reasons.It’s 235/40R18
Checked on that link and also from my-garagehonda when I was trying to buy winter tires
edit: oh nvm I just saw you wanted to do some downsizing(why though?)
Welcome to the forum @fnonca.I called the dealership yesterday and they confirmed it's fine.
And in fact that's what they are going to do there as well, use 16" for all 2022 civics winter tires
I'll just replace the windshield washer fluid with one that I know won't freeze when it gets to -20
I got on the Honda Canada Civic Touring page and they offer two winter tire options, both 16" wheels: Enkei and steelies