Speed limits on some portions of interstates in Idaho will go from 75 to 80 mph starting July 1.
The Idaho Transportation Department says Interstates 15, 84 and 86 will have speed limits increased where they pass through rural areas.
But interstate speeds in urban areas will mostly remain at 65 mph.
The agency says it has completed speed studies and engineering reviews ahead of the increase. It also has stockpiled new signs.
The agency says it's still studying raising speed limits on the state highway system from 65 to 70 mph.
Lawmakers approved the increases earlier this year.