From their FAQ (http://help.dwolla.com/customer/portal/articles/269223-how-can-i-delete-my-dwolla-account-):
Keep in mind that according to the “Data Retention” section in our Terms and Services we must keep all accounts in our system for at least 3 years. If you would like to remove the banking information from the account make sure to do so before you take either course of action.
URLS:
http://dwolla.com
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