Affidavits in India sit at the meeting point of several statutes rather than one dedicated Act. The administration of the oath itself is governed by the Oaths Act, 1969, which empowers courts, notaries and other authorised officers to administer oaths and solemn affirmations for both judicial and administrative purposes. The attesting officer's authority flows from the Notaries Act, 1952: a Notary Public appointed under that Act may attest documents for general, non-judicial purposes such as proof of address or identity, while an Oath Commissioner, appointed under the authority of the High Courts, attests affidavits meant for court proceedings within a defined jurisdiction. For an ordinary self-declaration used with a bank or a passport office, notarisation by a Notary Public is the standard route.
The evidentiary side changed recently and the change matters. The Bharatiya Sakshya Adhiniyam, 2023 replaced the old Indian Evidence Act, 1872 with effect from 1 July 2024, and it now governs how affidavits and electronic records are treated as evidence. Worth noting, the new Act expressly states that it does not apply to affidavits presented to a court or officer, which keeps affidavit practice largely procedural and continues the position under the former law. You can read the consolidated text on the official India Code repository for the Bharatiya Sakshya Adhiniyam.
The teeth come from the criminal code. A false sworn statement is perjury, and under Section 227 of the Bharatiya Nyaya Sanhita, 2023 (which replaced Section 191 of the old IPC), a person legally bound by oath who makes a statement he knows or believes to be false is said to give false evidence. The punishment under Section 229 can extend to seven years' imprisonment together with a fine, so an affidavit is never a place for loose drafting or convenient half-truths. Stamp duty on the affidavit itself is a State subject, payable on non-judicial stamp paper or e-stamp at the rate fixed by the relevant State Stamp Act.