A SWIFT code (or SWIFTBIC, as it’s sometimes known) is a code that helps overseas banks identify which bank to send money to.
A SWIFT code sometimes also called a SWIFT number is a standard format for Business Identifier Codes (BIC). Banks and financial institutions use them to identify themselves globally. It says who and where they are a sort of international bank code or ID.
These codes are used when transferring money between banks, particularly for international money transfers or SEPA payments. Banks also use these codes to exchange messages between each other.