The crash happened at about 6:30 a.m. at M-37 and M-46, near the roundabout in Casnovia Township. A driver who slid off the road told deputies a Chevrolet Trailblazer carrying six people also lost control and spun across the center lane and into the path of a pickup truck carrying three men.
Four people in the Trailblazer died and two others were taken to an area hospital. All three men in the truck were also taken to a hospital.
The victims were all Newaygo residents. They were identified as Erika Ceja, 34; Angelica Magana-Ceja, 44; Teresa Alvarez, 34; and Jessica Magana 22.
An off-duty nurse and off-duty Grand Rapids police detective stopped at the scene and assisted the victims.
All of the passengers in the SUV and pickup truck were heading to work at the time of the crash. Their names were not immediately released.
The road was closed for about five hours after the crash.