Idaho and Montana will join the ACE program on Aug. 6, meaning the system will be mandatory for truckers crossing the international border in those states.
ACE is the automated electronic manifest system that truckers entering the U.S. are supposed to file, rather than the old paper manifest.
Backers say the program speeds the flow of trucks and frees up the border patrol to concentrate on security.
Minnesota and Maine are scheduled to adopt the ACE system on Oct. 16. Most other states on both the northern and southern borders are already using the system.