The law
Income-tax Act 1961, Sec 244A(1)(b) (now Sec 437)
Interest on refund at 0.5% for every month or part of a monthSource
Income-tax Act 1961, Sec 244A(2) (now Sec 437)
Period of delay caused by the taxpayer can be excluded from interestSource
Income-tax Act 1961, Sec 245 (now Sec 438)
Refund can be adjusted against past tax duesSource
Income-tax Act 1961, Sec 139AA (now Sec 262) and CBDT Circular 03/2023
Inoperative PAN: no refund and no interest on refund until PAN becomes operativeSource
Income-tax Act 2025, Sec 536(2)
Refund proceedings for pre-2026 years continue under the 1961 Act; interest after commencement follows the new ActSource
Government fee
No fee for a refund reissue request. Source: https://www.incometax.gov.in/iec/foportal/help/all-topics/e-filing-services/refund-reissue-UM