If you live in Belgium and use a foreign broker like eToro, Degiro, Trading212, or Interactive Brokers, you are legally required to declare this account to the National Bank of Belgium (NBB) at the Central Point of Contact (CPC).
Any Belgian tax resident who held a foreign account at any point during the taxable period. This applies even if the account was empty or only open for a few days. It includes current accounts, savings accounts, and securities accounts (trading accounts).
Once you have declared the account to the NBB, you must also tick a specific box in your annual Personal Income Tax Return (usually code 1075). You do not need to enter the account details again in the tax return, just confirm that you have declared them to the CPC.
Disclaimer: This guide is for informational purposes only. Tax laws can change. Always consult an accountant.