All bitcoin providers must comply to a "Know your customer" policy for payments through iDEAL and Bancontact.
New customers need to have their bank account number verified before we can send the bitcoins. This process is only required once and takes just a few minutes. The last step in the verification process consists of making a bank transfer through online banking. We receive this bank transfer instantaneously if you have an ING, ABN, SNS or bunq bank account, or within a few hours if you use another bank. Belgian transfers may take up to a few days.
You can verify your bank account number beforehand, but you can also place an order first and go through the verification process later.
More information on the verification process.