In routine process Bank will deduct tax at source on fixed deposit interest, if it is above Rs. 10000. The TDS is deducted at the rate of 10% (if PAN not furnished the rate is 20%). So to get the income tax refund , you have to file the income tax return . To avoid this process, you have to declare that you have not any taxable income. The main and only purpose of these forms, is to submit declaration in writing in duplicate that there is not tax payable on his total income. In this case the payer shall not deduct any tax at source.
Form 15H must be used above 65 years old individual.
Previous year income should not be taxable.
Form 15H should be submitted before the first payment of interest on fixed deposit.
Form 15G is same like Form 15H difference is only that form 15G is for every individual below then 65 years.
The duty of submit these forms with assessee before end of the financial year or first payment of interest whichever is earlier.
The payer is under an obligation to deduct tax until the declaration in Form No. 15 G/15H is received and in the event that such form is not received till the end of the financial year, the failure to deduct tax amounts to violation of this section.