The monthly interest for a ₹15 Lakh fixed deposit depends solely on the interest rate offered by the bank or NBFC. Since there is no cap on interest rates, there is also no limit to the monthly interest you can earn. Higher interest rates result in higher monthly interest earnings.

Yes, the interest earned on your ₹15 Lakh fixed deposit is taxable under the head 'Income From Other Sources.' The tax rate is based on the income tax slab you fall under.

To open a fixed deposit, you need to provide proof of identity, address, photographs, and other KYC documents as required by the bank or NBFC.

Eligibility criteria may vary among banks and NBFCs. Generally, resident Indians, non-resident Indians, HUFs, trusts, sole proprietorships, and partnership firms are eligible to open a ₹15 Lakh fixed deposit.

For monthly interest payouts, use the formula for simple interest: (P × R × T) ÷ 100. For compound interest, the formula is: P × [(1 + R/100)^(T)] - P. Here, P  is the investment amount, R  is the interest rate, and T is the investment period in years.

Withdrawal penalties vary among FD issuers. Typically, withdrawing an FD prematurely incurs a penalty, which could result in a reduction of interest earnings.

If you do not renew your FD after maturity, the usually transfers the principal amount along with the interest earned to your linked savings account.

Deposits up to ₹5 Lakhs are insured under the Deposit Insurance and Credit Guarantee Corporation (DICGC) scheme, which covers FDs issued by banks.