What is Form 121 and how it will change TDS filing for taxpayers?

Form 121 is a new unified self-declaration replacing Forms 15G and 15H to help eligible taxpayers avoid tax deducted at source (TDS) on certain incomes if their total income is below the taxable limit. It allows individuals of all ages to declare non-deduction of TDS. Earlier, those below 60 submitted Form 15G, while senior citizens used Form 15H.