The US can now share the information received from airlines with a range of its security agencies more easily, including the CIA and FBI.
The US can request the data 72 hours before an aircraft takes off. Previously it got the information 15 minutes after take-off.
The US may not now destroy the information received on each passenger after 3½ years. This was a commitment under the first deal.
The EU will change the way airlines supply the data to the US. Currently, the US pulls data from European airline reservations systems but from next year airlines will send the data to the US instead.
The amount of data accessed by the US will not change.
The same 34 items will be available, including: the name of the passenger and other names on the airline ticket; the address of the passenger and the e-mail address; the date the reservation was made and the dates of intended travel; all forms of payment information including credit card details; contact telephone numbers; travel itinerary; and travel status of traveller.
The US has said it wants more information when the current deal ends in July 2007.