RALEIGH, N.C. (WTVD) -- Whether it's business or leisure, Karen Capps' travel routine includes a credit card and hotel rewards. "We do our fair share of traveling," she said.
Capps' travel habits are much like the 500 million customers inside Starwood reservations systems that were hacked by someone who now has access to names, birth dates, credit card information and even passport numbers.
"It's really important to stay on top of this type of breach where the information can't just readily be changed," says ABC News Chief Business Correspondent Rebecca Jarvis. "You're not going to go out and get a new passport number."
Add Marriott to the disturbingly growing list of massive hacks at companies consumers trust with sensitive personal details.
"I think it's something that I think about every time I pull my credit card out," Capps said. "I'm not sure what you do about it but it is a concern, especially when it's that large."
Concerned customers are being directed to an internet help desk: Info.starwoodhotels.com. The hotel chain is also sending emails to customers with more details.
Marriott International bought Starwood Hotels in 2016. The company says an investigation revealed the hacker breached Starwood's systems beginning in 2014. Starwood brands include W Hotels, St. Regis, Westin, Element, Aloft and Sheraton.
"We transitioned over to the Marriott reservation system October 30th. We've not had any issues," said Leon Cox, general manager at the Sheraton in downtown Raleigh.
Cox says he is unaware of any customers here affected so far by the breach.
"The only concerns we've had were just charges related to the transition of the (reservation) systems when the systems went down and the new system came back up," he said. "But nothing relating to people having their accounts hacked."
The Marriott breach is the largest consumer hack since Equifax when 148 million people were affected in 2017.
Teresa Bruton told us she was one of the many who got a letter warning her that her credit information could be compromised. She's been on guard ever since.
"I've actually got a credit freeze on all my credit so that even I can't get any sort of credit unless i unfreeze it. So that's what I looked at as a way to protect myself."
Experts are warning people to be on alert for scam callers -- people pretending to be from Marriott. If you get a call from someone who says they're with the company - you're urged to tell them you'll call them back on the company's main phone number.
Massive Marriott data hack: What customers need to know