Submission of letter for intimating the closure of trading window period wef 01st October 2026 till the expiry of 48 hours after the announcement of the Un-Audited Standalone and Consolidated financial results for the quarter ended 30th September 2026.

REF: CHEMFAB/SEC/2026-27 28th September, 2026 BSE Limited National Stock Exchange of India Limited Corporate Relationship Department The Manager, Listing Department Phiroze Jeejeebhoy Towers, “Exchange Plaza” Dalal Street, Bandra - Kurla Complex, Bandra (E) Mumbai- 400 001. Mumbai - 400 051 BSE – Scrip Code: 541269 NSE Symbol: CHEMFAB Dear Sir/Madam, Sub: Closure of Trading Window In line with the requirements of SEBI (Prohibition of Insider Trading) Regulations, 2015 (as amended) read with Company's "Code of Conduct for Prevention of Insider Trading" (“Code”), the trading window for dealing in the Company's Securities shall remain closed for all Directors, Designated Employees, other insiders of the Company and their relatives from Thursday, 01st October, 2026 till the expiry of 48 hours after the announcement of the Un- Audited Standalone and Consolidated Financial Results for the Quarter ended 30th September, 2026. The date of Board Meeting for considering the Un-Audited Standalone and Consolidated Financial Results for the Quarter ended 30th September, 2026 will be intimated separately in the due course. Request you to kindly take this on record. For CHEMFAB ALKALIS LIMITED Bharatraj Panchal Company Secretary FCS: 9828