Banco Santander, S.A. files 424B5

Banco Santander, S.A. is offering $ % Non-Step-Up Non-Cumulative Contingent Convertible Perpetual Preferred Tier 1 Securities. These securities are perpetual and may be redeemed at Banco Santander's option under certain conditions. In the event of a Trigger Event, the securities will be mandatorily converted into ordinary shares.