The ABA (American Bankers Association) is the Federal Reserve FEDLINE routing and transit number through which wire transfers are sent from one institution to another. It usually pertains to the main branch of the bank or credit union and should not be confused with third party branch ABA numbers. Contact the receiving institution for wire instructions including the ABA number. Each institution will have a specific ABA where wires should be directed.
Account numbers are more specific
a) For instance, every beneficiary has an individual account number with either the receiving bank, third party bank, credit union, or financial service institution. This is the final account where the funds are to be deposited.
b) Similarly, every third party has its own distinct account or ABA number that is what the receiving bank recognizes when channeling funds through to the beneficiary’s account number. Technically, it’s the third party’s account number with the receiving bank.