Please refer the enclosed disclosure.

IDFCFIRSTBANK/SD/171/2026-27 October 30, 2026 National Stock Exchange of India Limited BSE Limited Mumbai 400 051 Mumbai 400 001 NSE - Symbol: IDFCFIRSTB BSE - Scrip Code: 539437 Sub.: Disclosure under Regulation 30 of the SEBI (Listing Obligations and Disclosure Requirements) Regulations, 2015 Dear Sir / Madam, We wish to inform you that IDFC FIRST Bank has appointed Mr. Hardik Thaker as the Chief Information Security Officer of the Bank (“CISO”) and designated him as Senior Management Personnel (“SMP”), with effect from October 30, 2026, consequent to the resignation of Mr. Nitin Chauhan as the CISO. The details required pursuant to the applicable SEBI Master Circular is enclosed as Annexure 1. Yours faithfully, For IDFC FIRST Bank Limited Satish Gaikwad General Counsel and Company Secretary Encl.: As above IDFC FIRST Bank Limited Corporate Office: IDFC FIRST Bank Tower, (The Square), C-61, G Block, Bandra-Kurla Complex, Bandra (East), Mumbai - 400 051. Tel: +91 22 7132 5500 Registered Office: KRM Towers, 7th Floor, No.1, Harrington Road, Chetpet, Chennai - 600 031, Tamil Nadu. Tel: +91 44 4571 6477 CIN: L65110TN2014PLC097792 | E-mail: bank.info@idfcfirstbank.com | Website: www.idfcfirst.bank.in Annexure 1 Sr. No. Particulars Description Description 1. Rea son for change Appointment of Mr. Hardik Thaker as CISO, Resignation of Mr. Nitin Chauhan designated as SMP as CISO and consequent cessation as SMP, to pursue opportunities outside the Bank 2. Dat e of change October 30, 2026 The Bank has accepted the resignation of Mr. Chauhan, and his last working day with the Bank will be April 23, 2027 3. Brie f profile Hardik Thaker is currently with IDFC FIRST Bank as Not Applicable (in case of appointment) Deputy Chief Information Security Officer and leads the Bank’s cybersecurity transformation initiatives. He brings nearly two decades of experience across banking, financial services, regulatory institutions and global consulting, with expertise spanning cybersecurity transformation, AI, technology and cyber risk, cyber resilience and cloud security. Prior to joining IDFC FIRST Bank, he served as Executive Director, Enterprise Security & Resilience at GXS Bank, Singapore, where he contributed to building the security capabilities of its greenfield digital banks in Singapore and Malaysia. Previously, he held a security leadership and architecture role with the Monetary Authority of Singapore, Singapore’s financial regulator, with responsibilities spanning critical information infrastructure protection and the design of security architecture for commercial cloud adoption. Earlier in his career, he led IBM’s Security Strategy, Risk & Compliance practice across ASEAN, supporting organisations in strengthening their information security and risk capabilities. He has also worked with Deloitte and KPMG, advising clients on enhancing their cybersecurity maturity, including engagements associated with the Government of India’s National e-Governance Plan (NeGP). IDFC FIRST Bank Limited Corporate Office: IDFC FIRST Bank Tower, (The Square), C-61, G Block, Bandra-Kurla Complex, Bandra (East), Mumbai - 400 051. Tel: +91 22 7132 5500 Registered Office: KRM Towers, 7th Floor, No.1, Harrington Road, Chetpet, Chennai - 600 031, Tamil Nadu. Tel: +91 44 4571 6477 CIN: L65110TN2014PLC097792 | E-mail: bank.info@idfcfirstbank.com | Website: www.idfcfirst.bank.in He has contributed to industry and professional forums, including the Association of Banks in Singapore’s Standing Committee, as well as ISACA’s Emerging Technology Advisory Group and India Advocacy Task Force. He is a Certified Information Security Manager (CISM) and ISO 27001 Lead Auditor, and holds an MBA in Finance from Gujarat University and a degree in Mechanical Engineering. 4. Res ignation letter along Not Applicable Attached as Exhibit with detailed reason for the resignation 5. Dis closure of relationships Not Applicable Not Applicable between Directors (in case of appointment of a director) IDFC FIRST Bank Limited Corporate Office: IDFC FIRST Bank Tower, (The Square), C-61, G Block, Bandra-Kurla Complex, Bandra (East), Mumbai - 400 051. Tel: +91 22 7132 5500 Registered Office: KRM Towers, 7th Floor, No.1, Harrington Road, Chetpet, Chennai - 600 031, Tamil Nadu. Tel: +91 44 4571 6477 CIN: L65110TN2014PLC097792 | E-mail: bank.info@idfcfirstbank.com | Website: www.idfcfirst.bank.in Exhibit