The seller's bank routing details, needed only when their Payment Method is ACH so settlement money can be deposited straight to their account. As with the tax ID, you enter the full number once and afterward only see a masked version. Double-check it against a voided check or the seller's bank info before saving.
Banking details are sensitive. Enter them only from documentation the seller provides, and never read them aloud or share them. A wrong routing number can send a payout to the wrong bank.
Technical section
Data model, API, and internals — visible to developers.