The present invention provides various features for extracting a user's bank account information for use in facilitating the electronic transfer of funds to or from the user's bank account. One feature of the invention involves a method and system for extracting a bank routing number from character strings provided by a user from the face of a bank check. The method involves receiving from the user a magnetic ink character recognition (MICR) line. A contiguous string of characters within the MICR line that satisfies a checksum test is stored as the bank routing number for the user. A check number and an account number may also be received from the user. A test is performed to verify that the check number, the account number, and the bank routing number all coexist within the MICR line. Another feature of the invention involves a method and system for facilitating the transfer of funds between a buyer and a seller. A bank routing number is determined for the seller as noted above. A credit card account associated with the buyer is then charged to collect funds for purchasing one or more items from the seller, and at least a portion of the collected funds is deposited into the bank account of the seller using the extracted bank routing number.