In Belgium, you don’t need to worry. All motorways are free of tolls.
The only payment is required for the Liefkenshoektunnel near harbor of Antwerp. There is also a possibility to pay using your on-board unit called OBU, but this is recommended for frequent transit only.
Cash - 6.00 EUR
Cars up to 3,5 tons falls under category 1 and you will pay 6.00 EUR in cash.
Card - 4.95 EUR
With credit card (Visa, Eurocard – Mastercard or American Express) the price is lower, 4.95 EUR.
OBU - 3.56 EUR
(On-board unit)
You can find more information about the Tunnel of Liefkenshoek on the following link: