How Do Banks Dispute Charges and Investigate Claims

When you tell your bank a charge on your account is wrong, the bank files a formal claim called a chargeback through the card network (Visa, Mastercard, and the rest) and investigates on your behalf. That is the short answer to how banks dispute charges. The longer answer depends almost entirely on one thing: whether the disputed transaction was on a credit card or a debit card. The two follow different federal rules, different timelines, and very different liability limits.

Credit Card and Debit Card Disputes Are Not the Same

Credit card disputes are governed by Regulation Z, which implements the Fair Credit Billing Act.¹ Debit card disputes and other electronic fund transfers fall under Regulation E.² Both frameworks give you 60 days to report, but almost everything else differs.

For a credit card charge, you must send written notice to the specific billing inquiry address printed on your statement, not the payment address.³ A phone call alone does not preserve your rights under Regulation Z. For a debit card charge, the bank must accept either oral or written notice, though it can require you to follow up in writing within 10 business days.² Either way, writing it down protects you.

What to Send and How to File

Before you contact the bank, pull together what you need: your name, account number, the date the charge posted, the exact dollar amount, the merchant name as it appears on the statement, and a short explanation of why the charge is wrong. For credit card disputes, the FTC recommends certified mail with a return receipt so you have proof the issuer got your letter.³

Attach copies of anything that supports your version of events. Receipts, screenshots of the checkout page, delivery tracking, and emails with the merchant all become part of the bank’s file when it goes to the merchant’s payment processor. Send copies, not originals.

Most banks let you open a dispute inside the mobile app or online banking portal by tapping the transaction. You can also call customer service or walk into a branch. For a debit card, that phone call is enough to start the clock on the bank’s legal obligations. For a credit card, the call helps but does not replace the written notice to the billing inquiry address.

One narrow rule can trip up credit card disputes over goods or services (as opposed to outright fraud): federal law limits your right to raise merchant-based claims against your card issuer to situations where you first made a good-faith attempt to resolve the problem with the merchant, and the purchase exceeded $50 and happened either in your home state or within 100 miles of your billing address.⁴ Contact the merchant first, and keep a record of the attempt.

The 60-Day Deadline

For both card types, you have 60 days after the statement showing the disputed charge was sent to you to notify the bank.¹² Miss it and the consequences differ sharply by card type.

On a debit card, missing the 60-day window exposes you to unlimited liability for any unauthorized transfers that occur after that window closes and before you finally report.⁵ A thief could empty the account and you would have no legal right to recover the money.

On a credit card, missing the window means you lose the billing error protections of the Fair Credit Billing Act. The issuer can decline to investigate on that ground alone. For unauthorized charges specifically, though, the Truth in Lending Act’s $50 liability cap does not carry the same 60-day limit, so some protection may still exist even after the deadline passes.⁶

How Much You Could Lose

Credit Cards

Federal law caps your liability for unauthorized credit card charges at $50, no matter how much the thief spent, as long as the issuer gave you notice of your potential liability and a way to report the loss.⁶ Most major issuers advertise zero-liability policies that waive even that.

Debit Cards

Debit card liability is tiered and climbs the longer you wait:⁷

Report within 2 business days of learning about the loss, and your liability is capped at $50 (or the amount of the unauthorized transfers, whichever is less).
Report after 2 business days but within 60 days of your statement, and your liability can reach $500 for transfers after the two-day window.
Report more than 60 days after your statement was sent, and liability is unlimited for anything that happens after the 60-day mark and before you notify the bank.

Because debit transactions pull real money out of your account rather than adding to a balance you can dispute before paying, acting inside the two-business-day window matters more than any other single step.

What the Bank Does After You File

Debit Card Investigations

The bank has 10 business days from receiving your notice to investigate and decide. It must tell you the results within three business days of finishing, and correct any confirmed error within one business day.²

If the bank cannot finish in 10 business days, it can take up to 45 days total, but only if it provisionally credits your account for the full disputed amount (with any interest) within those first 10 business days.⁸ It also has to tell you within two business days of the provisional credit how much it credited and when, so you know the money is available while the investigation runs.

Some situations get longer clocks. For new accounts (first deposit within the past 30 days), the bank has 20 business days before the provisional credit is due and up to 90 days to finish. The same 90-day extension applies to international transfers and point-of-sale debit card transactions.²

Credit Card Investigations

The issuer must send written acknowledgment of your dispute within 30 days of receiving it, unless it resolves the whole thing in that window.¹ It then has two complete billing cycles, capped at 90 days, to finish.

Regulation Z does not require a provisional credit. What it does require is that you do not have to pay the disputed amount or related finance charges while the investigation is pending, and the issuer cannot try to collect it or report it as delinquent to the credit bureaus during that time.⁹¹⁰

The Decision and What It Means for Your Account

When the investigation ends, the bank issues a formal decision. If it confirms the charge was an error or unauthorized, any provisional credit on your debit account becomes permanent, or the credit card issuer removes the charge and any finance charges tied to it. You owe nothing for that transaction.

If the bank concludes the charge was legitimate, it must send a written explanation of its findings. For a debit card dispute, the notice must also tell you that you can request copies of the documents the bank relied on.¹¹ Any provisional credit is reversed. For a credit card dispute, the issuer tells you in writing what you owe and why, and you can request the supporting documents.³

If the Bank Denies Your Dispute

A denial is not necessarily the end.

Appeal a Credit Card Denial

Write to the issuer within the payment period it sets, or within 10 days of getting the explanation, whichever is later. State that you still dispute the charge and refuse to pay.³ The issuer may then report the amount as disputed to the credit bureaus, but it must also report that you disagree with its finding.

Complain to the CFPB

If you think the bank broke a federal rule during the dispute (missed a deadline, skipped the written explanation, ignored your evidence), file a complaint with the Consumer Financial Protection Bureau at consumerfinance.gov/complaint or by calling (855) 411-2372. The CFPB routes the complaint to the company and works to get a response, which companies generally provide within 15 days.¹² Include the dates, amounts, and copies of what you sent and received (the portal accepts up to 50 pages of supporting documents).

Fix a Damaged Checking Account Report

If the denial leads to negative information on your checking account consumer report through a service like ChexSystems, you can dispute that record with the reporting company directly. If the reinvestigation does not resolve it, you can file a brief statement of up to 100 words explaining your side, and it has to be included in future reports about you.¹³

1
eCFR. 12 CFR 1026.13 – Billing Error Resolution
2
eCFR. 12 CFR 1005.11 – Procedures for Resolving Errors
3
Federal Trade Commission. Using Credit Cards and Disputing Charges
4
eCFR. Part 226 Truth in Lending (Regulation Z)
5
Consumer Financial Protection Bureau. 1005.6 Liability of Consumer for Unauthorized Transfers
6
Office of the Law Revision Counsel. 15 U.S. Code 1643 – Liability of Holder of Credit Card
7
eCFR. 12 CFR 1005.6 – Liability of Consumer for Unauthorized Transfers
8
Consumer Financial Protection Bureau. 1005.11 Procedures for Resolving Errors
9
Consumer Financial Protection Bureau. 1026.13 Billing Error Resolution
10
Federal Trade Commission. Fair Credit Billing Act
11
eCFR. 12 CFR 1005.11 – Procedures for Resolving Errors
12
Consumer Financial Protection Bureau. Submit a Complaint
13
Office of the Law Revision Counsel. 15 U.S. Code 1681i – Procedure in Case of Disputed Accuracy