FATCA is real and it works: Indian IT department receives automatic data from USA, UK, Canada, Australia, UAE (from 2024), Singapore, and 100+ countries annually. Foreign banks report Indian customers. If you haven't disclosed: IT already knows. What must be disclosed: Any bank account where you are owner OR signing authority. ESOPs of foreign company (even unvested, even zero value). Foreign property. Shares in foreign company (even a startup equity grant worth $1). Trust as beneficiary. What details are needed: For each bank account: peak balance during year (highest balance on any single day), closing balance (March 31), interest earned, account number, SWIFT/IBAN, country. For ESOPs: company name, number of shares, acquisition date, cost, value.