ACA Premiums Jump 25%; Administration Acknowledges Extended Enrollment

WASHINGTON—The Obama administration Monday confirmed a 25% average jump in premiums for the Affordable Care Act’s benchmark health plans and acknowledged later sign-up deadlines for hundreds of thousands of people whose insurers are dropping their plans because of rising costs.

Sharper increases had already been posted in states around the country. Market-leader insurers that are continuing to sell coverage through HealthCare.gov or a state equivalent have been granted average premium increases of 30% or more in Alabama,...