Below is a brief summary of the difference between an ACH transfer and a wire transfer:
ACH Transfers. Interbank transfers (also known as ACH transfers), use a batch processing service provided by the Automated Clearing House that moves money multiple times per day between financial institutions.  Using Alliant’s Online or Telephone transfer services, you’re able to transfer money between your Alliant bank account and other bank accounts. Details about ACH transfers.
Wire transfers. A wire transfer is a direct bank to bank electronic transmission of money that requires both banks to verify the accounts and funds to be transferred. Wired money typically transfers in less than 24 hours, but timing varies between financial institutions’ transfer policies and procedures. Because there is additional work required by both financial institutions to complete a wire transfer, there are typically higher fees associated with wire transfers. Wire transfers are also used often for mortgage closings and car purchases. Details on sending a wire transfer from your Alliant account. Learn about wire error resolution and cancellation rights.