While Brussels is a highly "card-friendly" city in 2026, it is still advisable to carry a small amount of Euro cash. Most restaurants, shops, and hotels prefer contactless payments or major credit cards (Visa/Mastercard), but "cash only" signs still occasionally pop up at small bakeries, local markets, or older cafes in neighborhoods like the Marolles. Importantly, you will need small coins (usually €0.50 to €1.00) for public restrooms, where attendants (known as "Madame Pipi") maintain the facilities. Additionally, while the Brussels metro and trams accept contactless "tap-to-pay," having cash for a backup paper ticket is wise. Avoid large bills like €100 or €200, as many smaller vendors cannot or will not break them. Aim to have about €30–€50 in small denominations for minor tips, street waffles, and those essential restroom fees to ensure a smooth trip.