The most common reason a creditor knows where you bank is that you wrote the creditor a check from that bank. Creditors often ask debtors where they bank when debtors call to inquire about their accounts. However, by the time a lawsuit comes around, the debtor has forgotten that he or she has given this information to the bank.

Creditors also use a variety of other techniques, such as sending a debtor a small check, which the debtor cashes, perhaps thinking it is a rebate. The chased check provides the creditor with the name of the debtor's bank. Finally, the creditor may serve the debtor with post-judgment discovery, such as interrogatories, which the debtor is obligated to answer.

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