Are jeans and casual pants and skirts OK for dinner? Or should we plan on packing something dressier?

Well - that would depend on where you plan to eat. If it's a casual cafe jeans are fine. If it's the most elegant restaurant in town you would be out of place in jeans or eguivalent.

We were in Brugge last week and found many nice restaurants/cafes that we felt comfortable eating at in jeans and a nice sweater or shirt. That included most, if not all, of the restaurants surrounding the main market square.

I find jeans are rather heavy to take with and skirts, well they just don't suit me.

I'll have to ask my wife if she's planning on taking with a skirt.

I agree with nytraveler. We found Brugge to like most other places. Most places where you'd have lunch were fine with jeans, etc. In the evening, most places we found were dressier and jeans were not appropriate. Suits weren't required, but dark slacks and nice shirt/sweater were the rule (eg, navy dockers and turtleneck were OK)

We dress very casual in Belgium. Jeans and skirts, in combination with a dressier top or shirt, are OK for dinner.

don't worry about it. it's a very casual place...mostly tourists who are quite casual.

I would not dress casually if planning to go to one of the city's top restaurants like Den Gouden Harynck. It's definitely not a jeans type place. OTOH, most places in Brugge are used to every kind of outfit tourists wear, so decent casual clothes will be perfectly acceptable.