It depends. If it says "vegetarian" on the label, than most likely yes. "Vegetarian" would mean there are no meat products in it (many brands of refried beans contain animal lard) but there's always a chance there might be an milk product in there, so check the label. As for "fat-free" refried beans, this gets more tricky. You'd think because they're labeled "fat-free" that there is no animal lard (fat), but the FDA is pretty loose with terms so things that are labeled "fat-free" can still contain fat (lard) if the quantity is small enough. So it might still be there AND hidden under "natural seasonings" or "natural flavorings" or any term like that. Kosher symbols can sometimes be helpful in determining what is vegan or vegetarian but you can always call the manufacturer too (say you have an allergy).