Bank Dispute Letter Template for the United States

A Bank Dispute Letter is your formal tool for reporting an unauthorized transaction, a fraudulent charge, a billing error, or another problem with your bank or card company. Under United States federal law, this document triggers specific consumer protections and starts the bank's mandatory investigation. When you submit a properly formatted letter, you activate rights under the Electronic Fund Transfer Act, Fair Credit Billing Act, and Truth in Lending Act. It works for personal customers and small business account holders alike.

How do I write a dispute letter for an unauthorized transaction?

State the problem in the first line so the bank can see what you need help with. Include your name and account or card number, then identify the charge you are questioning by date, amount, and merchant. Explain clearly that you did not authorize the transaction, or that it is fraud, and ask the bank to reverse it and refund your account. Attach anything that supports your case, such as statements, receipts, or a police or fraud report. A worked example: "On March 3, 2025, a charge of $412.00 to 'Northgate Supplies' appeared on card ending 4471. I did not make or authorize this purchase and believe it is fraudulent. Please remove the charge and credit my account." Keep the tone factual and specific so the card company can act on it without follow-up.

Sending the letter by mail, online, or email

Send the letter to the address the bank designates for billing inquiries, which you can usually find on the back of your statement or in the disputes menu of your online banking site. Some banks also accept a secure message or an email through their online portal. Whichever route you use, enclose copies of your supporting documents (never the originals) and keep a copy of the letter for your own records. Certified mail is the safest option because it gives you proof the bank received it and started the clock.

When do you need this document?

You need a Bank Dispute Letter when you see an unauthorized charge on your account, notice a billing error on a credit card statement, or run into a problem with an electronic transfer. This includes a merchant charging the wrong amount, a duplicate appearing on your statement, or goods and services you paid for but never received. The letter also helps when an ATM transaction fails but money is still debited, or when an automatic payment continues after you cancelled a service. Time is critical. You typically have only 60 days from receiving your statement to challenge a credit card charge and 60 days from the transaction date for debit card claims.

What should the letter include?

To trigger federal protections, your letter must carry a set of core details, so present them clearly rather than leaving anything out:

• Your full name and the account or card number involved.
• The date, amount, and merchant for each charge you are questioning.
• A short explanation of why the transaction is unauthorized, fraudulent, or in error.
• The resolution you want, usually a refund or reversal.
• Copies (not originals) of any supporting documents, such as receipts or a fraud report, enclosed with the letter.

Once the bank receives your letter, it has legal obligations. It must acknowledge the complaint, generally within 30 days, and investigate within set timeframes. For a credit card dispute under the Fair Credit Billing Act, the card company cannot report you as delinquent to credit agencies while it investigates. For a debit card claim under the Electronic Fund Transfer Act, the bank may need to give provisional credit during the review. Keep records of every call and letter, and send yours by certified mail so you can prove the bank received it.

How does the bank investigate, and what are the deadlines?

Federal law sets strict timelines. Under the Electronic Fund Transfer Act, reporting an unauthorized electronic transaction within 60 days of your statement limits your liability to $50. The Fair Credit Billing Act gives similar protection for credit card disputes when you notify the bank in writing within 60 days. Send the letter to the address the bank designates for billing inquiries, not a general branch address, since only that address starts the clock. Banks must investigate within specific windows, generally 30 days for credit cards and 10 business days for debit cards, though extensions can apply for complex cases. Regulation Z lets you withhold payment on the disputed amount while the credit card investigation runs.

Related complaint and dispute documents

If the problem sits specifically with a card charge, you may prefer the focused unauthorized transaction on credit card complaint letter. You can also browse the wider dispute letter templates to find the format that fits your situation.