The counterfeit-check scam exploits the gap between availability and verification.

Money appearing in an account does not necessarily mean the check was authentic.

A stranger sends a check and asks the recipient to deposit it, keep a portion and return the rest. The story may involve remote work, a prize, an overpayment, mystery shopping or buying supplies for a new job.

The balance may become available before the bank determines that the check is counterfeit. That delay is the mechanism of the scam: the recipient sends real money while the fraudulent deposit is still being processed, then remains responsible when the check is reversed.

Why the bank balance is misleading

Funds-availability rules can make deposited money usable before every element of a check has been fully authenticated. Counterfeit documents may closely resemble legitimate checks and postal money orders. If the original account information is stolen or altered, discovery can take time.

A bank making funds available is not a guarantee that the check has finally cleared. The sender’s instruction to return money, buy gift cards, purchase cryptocurrency or forward packages transfers the immediate risk to the recipient.

Patterns that should stop the transaction

• A new employer sends a check before work begins and asks the recipient to buy equipment.
• A buyer pays more than the agreed price and requests a refund of the difference.
• A prize requires depositing a check and sending fees elsewhere.
• A stranger offers a commission for moving money through a personal account.

What to do

Do not send money or merchandise against an unexpected check. Contact the issuing bank using independently verified information and tell your own bank why the payment is suspicious. Preserve the envelope, check, messages and transaction instructions. When the U.S. Mail is involved, report it to the Postal Inspection Service; related fraud can also be reported to the FTC.