Credit cards and debit cards are covered by different federal laws, with different protections and different deadlines. That difference is the single most useful thing to know here.
Two Laws, Two Levels of Protection
Credit card transactions fall under the Fair Credit Billing Act. Debit card transactions and other electronic transfers fall under the Electronic Fund Transfer Act and its implementing rule, Regulation E.
The practical consequence is about whose money is missing while the dispute is investigated. Dispute a credit card charge and you are withholding payment on a bill — the money has not left your account. Dispute a debit card transaction and the funds are already gone from your checking account, and they stay gone until the investigation resolves.
That asymmetry is why the general recommendation is to use a credit card for anything carrying risk — online purchases, unfamiliar merchants, travel, anything where a dispute is plausible. It is not that fraud is less likely; it is that the consequences of fraud land differently.
A distinction worth keeping straight: unauthorised fraud and a billing dispute over a legitimate purchase are different processes, even though both are often called disputes. Fraud means you did not authorise the transaction. A billing error means you did, and something about the charge or the goods is wrong.
Why Speed Matters Most on Debit
Under Regulation E, your maximum liability for unauthorised debit transactions depends on how quickly you report — and the tiers are steep. Report promptly after discovering the problem and your exposure is limited to a small amount. Delay and the cap rises substantially. Delay long enough after a statement showing the transaction and you can be liable for the full amount taken.
This is the most consequential detail in consumer banking protection, and it is almost never mentioned when people are advised to “check your statements.” The reason to check them is that a clock is running.
Credit card liability for unauthorised use is capped far lower by statute, and in practice most issuers apply zero-liability policies. The urgency is real there too, but the downside of a delay is smaller.
The rule that follows: monitor the debit account closely, enable transaction alerts, and treat an unrecognised debit charge as something to report today rather than this week.
How to Report It
Call the number on the back of the card immediately and report the transaction as unauthorised. Ask them to freeze or replace the card if the details have been compromised.
Follow up in writing. A phone call starts the process; written notice creates the record and, for billing errors on a credit card, the written dispute is what triggers the formal procedure with its defined timelines. Send it to the address the issuer designates for billing disputes, which is not necessarily the address you send payments to.
Include the specifics: the account, the date and amount of each disputed transaction, why it is unauthorised, and when you discovered it. Keep a copy of everything and note the date you sent it.
For a debit dispute, ask specifically about provisional credit — under Regulation E, if the investigation extends beyond a defined period, the bank is generally required to credit the disputed amount to your account while it continues. Ask when that would apply to your case.
Billing Errors Versus Goods That Never Arrived
Separate from fraud, the Fair Credit Billing Act covers billing errors on credit accounts: charges you did not make, wrong amounts or dates, charges for goods you never received or that were not as described, and failures to post a payment or credit.
There is a deadline here too. You generally must dispute in writing within a set period after the statement containing the error was sent, so the statement date is the clock rather than the transaction date.
While a billing error is under investigation, you are not required to pay the disputed amount, and the issuer cannot report it as delinquent. Keep paying the undisputed portion of your balance, though — the protection covers the disputed item, not the whole bill.
The related tool for goods and services is a chargeback, processed through the card networks. In practice, contacting the merchant first often resolves things faster than a formal dispute, and a documented attempt to resolve it strengthens your position if you do escalate.
When the Bank Says No
You are entitled to an explanation of the investigation’s outcome, and to the documents the decision relied on. Ask for them, in writing.
If you disagree, escalate rather than accept. Provide any evidence you did not supply the first time, and ask for the dispute to be reopened. Persistence matters, because a first-pass decision is often made on thin information.
Then file a complaint with the Consumer Financial Protection Bureau, which routes it to the institution and requires a substantive response. Your state attorney general and state banking regulator are additional avenues, and state law sometimes provides protections beyond the federal minimum.
If the fraud extends past a single transaction — accounts opened in your name, several institutions involved — treat it as identity theft. Report it through IdentityTheft.gov, which produces a recovery plan and an official report you can send to creditors, and place a credit freeze at each of the three bureaus to stop further accounts being opened. The freeze is free, and it is the single most effective step available.
