After the maturity of your fixed deposit, you will get the return that was deposited to your savings account, which you have chosen for the period structure of monthly or quarterly basis. Again if you desire to re-invest the same amount which will be additionally invested and the returns will get the gain in term of compound interest.
Nevertheless one must know that apart from investing in long tenure you cannot apply for a loan with the tax saving FD. Then in terms of the medium to long term prospect like five years, and also if you are looking for a secure and tax-free return and getting good returns on your money, then the tax savings fixed deposit becomes more than useful.
The Fixed deposits might not give you a good return like that you used to get earlier like 14% but if you look and take into consideration of the income tax-free returns, the tax saving Fixed Deposits have surely developed some lost reputation that the FDs once was.
No need to worry about a huge sum of money as you can start with as little as INR 100 and for older citizens, the returns are slightly higher based on the bank/ NBFC that you are investing the fixed deposit. Recently, they have added a sweep-in facility which again is not relevant for the tax saving fixed deposit and also you cannot even link that to your savings account. Not only that the extra amount that in your savings account cannot be moved to the tax savings FD and there is no overdraft advantage too.