Who is liable for a forged or altered check?
When a check is forged or altered and the money leaves your account, the first question is who absorbs the loss: your bank or your business. The answer comes from the Uniform Commercial Code (UCC), the model law that most U.S. states have adopted for negotiable instruments and bank deposits. The rules are not simple, and they reward the customer who watches the account and punishes the one who does not.
This page is general educational information, not legal advice. The exact rules depend on your state's version of the UCC, on court decisions in your jurisdiction, and on the deposit agreement you signed. Consult an attorney and read your deposit agreement before relying on anything here.
The starting point: UCC 4-401 and "properly payable"
Under UCC 4-401(a), a bank may charge your account only for an item that is properly payable. An item is properly payable if it is authorized by the customer and is in accordance with the agreement between the customer and the bank. A check carrying a forged drawer signature, or a check whose amount or payee was altered after you wrote it, is generally not authorized by you. Because it is not properly payable, the bank usually has to recredit your account. So the default rule starts in the customer's favor: the bank eats the loss on a true forgery.
That default does not hold if your own conduct contributed to the fraud, or if you sat on the problem. Two other sections, 3-406 and 4-406, can move the loss back to you.
UCC 3-406: negligence that contributes to the forgery
Under UCC 3-406(a), a person whose failure to exercise ordinary care substantially contributes to a forged signature or an alteration is precluded from asserting that forgery or alteration against a bank that paid in good faith. In plain terms, if your sloppiness helped the fraud happen, you can lose the right to push the loss onto the bank. Common examples include leaving signed blank checks accessible, failing to reconcile, or ignoring obvious gaps in check stock.
The preclusion is not always total. UCC 3-406(b) adds a comparative negligence rule: if the bank that paid the item also failed to exercise ordinary care, and that failure contributed to the loss, the loss is allocated between the two parties according to how much each one's failure contributed. So a careless customer and a careless bank can end up splitting the bill.
UCC 4-406: your duty to examine statements and the one-year cutoff
UCC 4-406 imposes a duty on you, the customer. When the bank sends or makes available a statement and the items (or enough information to identify them), you must examine it with reasonable promptness and promptly notify the bank of any unauthorized signature or alteration you discover.
- If you fail this duty and the bank proves it suffered a loss as a result, you can lose the right to claim that item.
- There is a same-wrongdoer rule: if the same person forges or alters a series of items, you generally cannot recover for the later ones once you have had a reasonable period (the statute sets a maximum of 30 days) to examine the statement and report the first one, but you failed to do so.
- Comparative negligence applies here too. If you failed to examine and report, but the bank also failed to exercise ordinary care in paying the item, the loss is allocated between you according to how much each failure contributed, unless the bank did not pay in good faith.
The hardest deadline is in UCC 4-406(f). If you do not discover and report your unauthorized signature or any alteration within one year after the statement or items are made available, you are barred from making the claim against the bank, no matter how careful or careless either side was. This one-year cutoff is absolute, so reconciling accounts on a regular schedule is not optional bookkeeping. It is the difference between recovering and losing the money.
How positive pay shifts the ordinary-care analysis
Positive pay is a service in which you send the bank a check issue file listing each check you wrote, usually the check number, amount, issue date, and often the payee. The bank matches every presented check against your list and flags anything that does not match as an exception for you to pay or return. It is one of the most direct defenses against forged and altered checks.
Positive pay also matters to the liability question, because "ordinary care" is judged by what a reasonable customer in your position would do. Courts have looked at whether a customer was offered positive pay and declined it. In Cincinnati Insurance Co. v. Wachovia Bank (D. Minn. 2010), a check was altered and paid, and the customer had not enrolled in the bank's positive pay program. The court found that the bank's deposit agreement validly shifted the loss to the customer who had declined the offered fraud-prevention service. The lesson is not that refusing positive pay always makes you liable. It is that the refusal can become part of the ordinary-care and contract analysis, and your deposit agreement may say so explicitly.
If you do use positive pay, the exact file layout is set by your bank and is account-specific. We do not publish invented field positions. You can build a correct file with the free positive pay file generator, review field-by-field guidance in the positive pay file format reference, and if your bank uses a custom layout, match it with the format builder. For background on the protection itself, see what is positive pay and how positive pay stops check fraud.
What this means in practice
- Reconcile fast. The 30-day same-wrongdoer window and the one-year hard cutoff in
4-406reward prompt review and punish delay. - Control your check stock and signatures. Negligence that contributes to a forgery can preclude your claim under
3-406. - Read your deposit agreement. Banks can vary some default rules by contract, and a declined positive pay service may be referenced there.
- Use the fraud tools offered to you. Declining an available defense can weigh against you in the ordinary-care analysis.
Again, this is general information and not legal advice. The outcome of any real dispute turns on your state's UCC, the facts, the case law where you are, and your deposit agreement. Talk to an attorney about your specific situation.