Affidavit

An affidavit is a sworn statement made in writing and signed before an official authorized to administer oaths, such as a notary public, commissioner of oaths or certain court officers. By signing an affidavit, the person making it, called the deponent, confirms under penalty of perjury that the statements in it are true, which gives the document legal weight that an ordinary unsworn letter does not have.

In banking, affidavits are used in a range of everyday situations: a customer disputing a forged check, a family member confirming facts needed to access a deceased account holder's funds, or a borrower attesting to the source of a large deposit used for a mortgage down payment, something lenders increasingly require as part of anti-money-laundering checks.

An affidavit is a promise backed by the threat of criminal punishment for lying. That extra weight is exactly why banks, courts and government agencies accept it in place of more time-consuming proof, provided the person signing understands the seriousness of what they are swearing to.

• An affidavit of forgery, in which a customer swears that their signature on a check was not genuine, supporting a claim to have the item reversed.
• An affidavit of lost instrument, used when a customer needs to replace a lost certified check or bank draft and must indemnify the bank against the original being presented later.
• An affidavit used alongside, or sometimes instead of, a grant of probate to let a bank release a small estate's funds without full court proceedings.

Because signing a false affidavit is itself a criminal offense in most jurisdictions, banks treat a properly executed affidavit as strong, if not conclusive, evidence when deciding whether to reverse a disputed transaction or release funds. This formal weight is precisely what distinguishes an affidavit from an ordinary signed letter, and it is why banks generally insist on a notarized affidavit rather than accepting an unsworn written explanation for higher-risk requests such as fraud claims or estate access.

An affidavit is strong evidence, but it is not automatically conclusive proof, and a bank or court can still investigate further or reject a claim if other evidence contradicts what was sworn. Large or unusual claims, such as a significant disputed transaction, often require an affidavit alongside supporting documents such as police reports or transaction records rather than the affidavit standing entirely on its own.

International transactions sometimes require an affidavit to be apostilled or otherwise authenticated for use in a foreign country, adding an extra administrative layer beyond simply finding a local notary, since a bank or court in one jurisdiction will not automatically accept a sworn document notarized under a different country's legal system without this additional certification.

Most jurisdictions keep notarization fees modest and allow a wide range of professionals, from bank staff to pharmacists in some countries, to act as notaries, which keeps affidavits a relatively accessible legal tool for ordinary banking disputes rather than something requiring expensive legal representation just to produce the sworn document itself.

Some jurisdictions now permit remote online notarization, allowing an affidavit to be sworn and notarized via video link rather than in person, a development that has made the process considerably more convenient for people in remote areas or unable to travel to a notary's office.

Because an affidavit is sworn under penalty of perjury, knowingly making a false statement in one can result in criminal charges separate from, and often more serious than, whatever underlying financial dispute the affidavit was originally meant to resolve.

Many jurisdictions allow a simplified, affidavit-based process for settling a small estate below a defined value threshold, letting a surviving family member access a deceased person's bank account by swearing an affidavit of entitlement rather than going through a full, often lengthy, grant of probate. This small-estate affidavit procedure exists specifically to spare grieving families the cost and delay of formal court proceedings when the amount involved does not justify it. Banks typically require the affidavit alongside a death certificate and some proof of the signer's relationship to the deceased, and they retain discretion to insist on a full grant of probate anyway if the estate is more complex than the simplified process is designed to handle.