All flights to/from the United States are subject to KLM 24-hour cancellation policy. This complies with the rules set forth by the U.S. Department of Transportation for all flights to or from the United States.
According to this policy, you are entitled to a full refund if you:
Purchase a flight to
Or from the United States on KLM.us
Cancel it within 24 hours and
Request a refund.
Mention the Customer First Program in the email's subject line and provide your name, flight number, departure date, and reservation number.