The increases follow last year’s sharp rise in premiums. Insurers have cited higher health care costs in seeking new rates, which are subject to review by Tennessee regulators and approval by the U.S. Centers for Medicare and Medicaid Services.

UnitedHealthcare’s Tennessee increases are expected to average 15% to 20%, said Leigh Carl, the company’s agency manager for the East region. Federal data show increases of 25.6% to 39% for some of its individual plans.

Other proposed Marketplace changes vary by company and plan. Oscar’s rates range from just over 11% to more than 25%; Alliant Health Plans’ individual-plan increases range from slightly above 16% to 27.5%. BlueCross BlueShield of Tennessee said its average increase is 10.5%, though some plans could rise as much as 23.4%. Ambetter plans are expected to increase by 9.45% to 14.57%.

The figures are not uniform increases for every customer: costs depend on the plan a person chooses and other factors. Some BlueCross plans are expected to cost less, while many consumers may see higher bills. Employer-sponsored coverage is also expected to become more expensive. Small-business plans covering companies with 50 or fewer workers face estimated increases of 10% to nearly 17%. For workers at larger companies, the amount passed on to employees will depend partly on how much employers contribute.

Marketplace open enrollment starts Nov. 1. People who select a plan by Dec. 15 can generally have coverage begin Jan. 1. The enrollment period continues through Jan. 15, but plans selected after the December deadline generally will not start until Feb. 1.

Cigna Health and Life Insurance is leaving Tennessee’s Marketplace. Federal officials have assigned its current members to other insurers to help avoid a gap in coverage, but customers can choose a different plan by Dec. 15 for coverage beginning Jan. 1. Cigna members should review notices from the company, the federal Marketplace and their assigned insurer.

Some households may qualify for federal premium tax credits that lower monthly bills, as well as additional assistance with deductibles, copayments and coinsurance. Eligibility depends on household circumstances and income. Children may qualify for Medicaid or the Children’s Health Insurance Program even if their parents do not qualify for Medicaid.

In Tennessee, the children’s program is called CoverKids. It provides coverage for eligible children through age 18, including dental and vision benefits. Uninsured pregnant women who do not qualify for TennCare may also be eligible for prenatal, delivery and 60 days of postpartum care.

Free help comparing Marketplace plans is available from insurance navigators, including through the nonprofit GetCoveredTenn. Residents can also find enrollment information at HealthCare.gov or contact the Marketplace at 800-318-2596. The Tennessee Department of Commerce and Insurance offers consumer guidance on health coverage.