What each form does
Form 15CA is filed by you (the remitter) on the income-tax portal and has Parts A to D depending on the amount and whether it is taxable. Form 15CB is issued by a chartered accountant who certifies the nature of the payment, its taxability, the rate of TDS and any DTAA relief applied.
When you actually need them
You need 15CA Part C with a 15CB when the remittance is chargeable to tax and above ₹5 lakh in the financial year. Smaller or non-taxable payments, and items on the RBI’s specified exempt list, need only a simpler part or nothing at all. A repatriation from your NRO account usually needs both. Thresholds and the exempt list can change — confirm the current rules.
A worked example
You want to repatriate ₹80 lakh of property proceeds from your NRO account. Your CA reviews the sale, confirms the capital-gains tax and TDS have been dealt with, and issues Form 15CB. You then file Form 15CA referencing it, and the bank releases the funds. Our NRI repatriation & FEMA service prepares both.