The interest rate on Public Provident Fund (PPF) is higher than that of FD or RD, i.e. by depositing small amount every month, big returns can be taken.
PPF offers an interest rate of 7.1% per annum which is completely tax free under section 80C of the Income Tax Act.
The minimum deposit amount can be Rs 500 and maximum Rs 1,50,000 per annum. The account remains blocked for 5 years.