Hackers accessed the passport numbers of 5.25 million people during its major data breach last year, Marriott has revealed.
In an update on Friday, the world’s biggest hotel company said that around 383 million customers were affected by a data breach in November, lower than the 500 million initially reported.
The vast number of people affected still places the Marriott data breach among the biggest hacks of personal data ever to affect one company.
The data stolen included passport numbers, emails, dates of birth, gender and mailing addresses.
Marriott now believes that 8.6 million encrypted payment cards were involved in the hack on its Starwood room reservation network.
The US hotel chain said that cyber attackers were also able to access the encrypted passport numbers of 20.3 million customers, but has no evidence that they were able to bypass the code and access the confidential information.
The US hotels giant, which operates about 6500 hotels in 127 countries, has not said how many Britons were among the victims of the data breach.
Reservations at all its Starwood properties – which include the Park Lane Sheraton Grand, Westbury Mayfair and Le Meridien Piccadilly in London – were affected.
Arne Sorenson, chief executive of Marriott, said: “We want to provide our customers and partners with updates based on our ongoing work to address this incident as we try to understand as much as we possibly can about what happened.