Banco Santander, S.A. Share Buyback Program Update

This report details the transactions made by Banco Santander, S.A. under its share buyback program between September 10 and September 16, 2026. The total cash amount spent on repurchasing shares during this period was €558,894,930, representing approximately 30.6% of the program's maximum investment. As of September 16, 2026, the bank had repurchased approximately 18.2% of its outstanding shares. The report includes a detailed breakdown of the number of shares purchased, the weighted average price, and the trading venues for each transaction. This information is provided in compliance with EU Market Abuse Regulations. The report is signed by Pedro de Mingo Kaminouchi, Head of Corporate Compliance.