Alteration

An alteration is any change made to the date, amount, or payee name on a check or other negotiable instrument after it was originally written, without the authorization of the person who issued it. It is one of the oldest and still most common forms of check fraud, ranging from crudely changing a number to the more sophisticated check washing, where chemicals are used to erase and rewrite the original details entirely.

Banks are generally liable for paying an altered check if they fail to detect an alteration that a reasonably careful examination should have caught, though the account holder also has a duty to review statements promptly and report discrepancies within a limited window, commonly 30 to 60 days, or risk losing the right to claim a refund for the loss.

An alteration is simply tampering with a check after it leaves the writer's hands, so that it pays out a different amount, to a different person, than was originally intended. Even a small, carefully disguised change can cause a significant loss if it slips past the bank's checks.

• Comparing the written and numeric amounts on the check for inconsistency.
• Automated image analysis that flags irregular ink patterns or erasures invisible to the naked eye.
• Positive pay services, where a business pre-registers the checks it issues so the bank can flag anything that does not match.

Writing checks in permanent ink, filling all available space on the amount lines, and avoiding gaps that could be used to insert extra digits are the most basic consumer protections. Businesses handling large check volumes increasingly rely on positive pay and gel-pen-resistant check stock specifically designed to make chemical washing visible under normal lighting.

Liability for an altered check generally depends on whether the bank's handling met the standard of ordinary care, and whether the account holder's own negligence, such as leaving blank space on a check, contributed to the alteration succeeding. Courts in many jurisdictions apportion the loss between the bank and the account holder when both parties bear some responsibility for the fraud going undetected.

Most jurisdictions apply a comparative negligence standard to altered checks, meaning liability is apportioned between the bank, which may have failed to catch an obvious alteration, and the account holder, who may have made the alteration easier by leaving blank space or using erasable ink, rather than placing the full loss automatically on either party.

A business that issues a high volume of checks faces proportionally greater exposure to alteration fraud, which is why many businesses have shifted to electronic payment methods such as ACH transfers for payroll and supplier payments specifically to reduce the number of physical checks in circulation that could be intercepted and altered.

An altered check differs from a wholly counterfeit check, which is fabricated from scratch rather than modified from a genuine original; banks apply somewhat different detection techniques to each, though both ultimately rely on close examination of the physical and printed characteristics of the instrument presented for payment.

Some businesses purchase specific fidelity or crime insurance covering losses from check fraud, including alteration, recognizing that even careful internal controls cannot eliminate the risk entirely for a business that still issues a significant volume of paper checks.

A successfully washed and altered check can result in a loss far exceeding the original check's intended amount, since criminals typically rewrite the amount to the maximum they believe can plausibly clear without immediately triggering a bank's fraud controls. Businesses that issue many checks, particularly for payroll, have increasingly adopted positive pay arrangements specifically because the potential loss from even a single successful alteration scheme can be substantial. Consumers who discover a bank statement showing a check cleared for an unfamiliar, inflated amount should contact their bank immediately, since most jurisdictions impose a relatively short window, often measured in weeks rather than months, for reporting an altered check before liability can shift toward the account holder for failing to catch it sooner.