Premiums are expected to rise an average of 27 percent for the hundreds of thousands of Michigan residents who buy their own health insurance.
Consumers eligible for income-based tax credits will be protected from the premium increases.
The state Department of Insurance and Financial Services published the rates on Wednesday.
Enrollment for 2018 begins in a week.
The state says the premiums are higher than expected because President Donald Trump recently ended cost-sharing payments to insurers for providing lower-income customers discounts on out-of-pocket costs.