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Payment Notary

Seal a supplier or landlord's bank details the first time you receive them. If an email later arrives saying "our bank details have changed," check it against the seal before you pay a penny. That switch is one of the most common invoice fraud moves there is.

Your bank details never leave your browser

The account name, sort code and number you paste are hashed on your own device before anything is sent. Red Flag never receives or stores the actual numbers, only a fingerprint of them, sealed with an independent third party timestamp. Nobody, including us, can read back what you sealed.

This is a fingerprint match, not a bank verification service — it tells you whether the details match what you sealed before, not whether an account is genuine. If they don't match, that is the signal to stop and check by phone before paying.