Durham-based Blue Cross and Blue Shield of North Carolina requested a 22.9 percent average rate increase for health plans it sells on the ACA exchange.
The insurer attributed most of the hike to funding for cost-sharing reduction payments, which BCBSNC projects will not be provided in 2018.
BCBSNC said were it known if the cost-sharing reductions will be fully funded next year, its "requested increase would have been 8.8 percent."
The payer said a tax on health insurers and increased medical costs also contributed to the change. BCBSNC said it is still unsure if it will participate in the 2018 ACA exchanges.