Washington officials will set up insurance markets in states that chose against participating, as at least 19 Republican governors have indicated.
The federal announcement Thursday comes as open enrollment for millions of uninsured Americans is less than 10 months away — Oct. 1.
Utah officials will have some significant work ahead to make sure the marketplace conforms to federal rules, said Jennifer Tolbert, director of state health reform at the nonpartisan Kaiser Family Foundation. Creating the navigation component in particular will be time-consuming, she said.
"It will be a heavy lift for the state," Tolbert said. "But they have the infrastructure for the exchange up and running already. They will able to build on that."
Herbert last month announced his plan to submit the state's existing exchange for federal approval, saying he found several problems with federal plans and that he preferred a state-based approach to stay true to "Utah principles."
Also, in a letter to President Barack Obama on Dec. 10, the governor wrote that he wanted "the Utah exchange to survive and thrive as we originally envisioned it."
"In fact, I hope it becomes a model for other states," he added.
Utah, along with Massachusetts, pioneered online health insurance marketplaces designed to reduce confusion and anxiety for individuals, families and businesses purchasing health care coverage.
They are meant to have the feel of an online travel site, such as an Expedia or Orbitz.
Under the health care law, which Obama signed in 2010, about 8 in 10 customers in the new marketplaces will be eligible for federal aid to help pay their premiums.
Small businesses will have separate access to their own exchanges.
Utah officials have said they plan to have the individual marketplace up and running by Jan. 1, 2014, when coverage would take effect.
Associated Press writer Ricardo Alonso-Zaldivar in Washington contributed to this report.