I've paid my invoice or payment invitation. Why is it still marked as unpaid?

If you pay your invoice or payment invitation online (using Bancontact, Visa, MasterCard, ...) the payment is processed immediately. When paying with bank transfer, it takes longer: up to five working days. 

Check the structured notification on your invoice or payment invitation. A payment with an incorrect structured notification might not get processed. If that happens, it is automatically refunded to you.