Obamacare consumers will face double-digit rate hikes for 2017, with most states looking at an average 25 percent increase, according to one estimate.

The premium spikes come as the Obama administration will boost outreach this open enrollment season, which starts Nov. 1, to reach more people who are uninsured. Opponents of the law point to the premium hikes as evidence the law isn't working, while the Obama administration said healthcare would remain affordable for most customers thanks to tax credits.

An independent estimate from the website acasignups.net found that 41 states approved an average rate increase of about 25 percent. That figure includes Affordable Care Act-compliant individual plans that are sold off the law's exchanges.

The individual market is for people who don't get insurance through their job and includes Obamacare's marketplaces.

Charles Gaba, who runs the website and is an Obamacare supporter, said in a post Wednesday that the 25 percent hike will likely hold.

"Barring any dramatic last-minute development in one or more large states, national speaking, 25 percent is where unsubsidized, ACA-compliant individual market rate hikes are for 2017," he said.

The increases can vary depending on states and individual plans. Some states are seeing increases as high as 75 percent.

Arizona's insurance regulator announced rates for Blue Cross Blue Shield of more than 50 percent. The insurer will cover all counties in the state except for Maricopa County, which includes Phoenix.

The insurer Centene will cover Maricopa, where Arizona's insurance regulator approved a 74 percent rate hike for the insurer's Obamacare plans.

Other states, such as Minnesota, are also seeing increases of 50 percent or more.

In Oklahoma, only one carrier, Blue Cross Blue Shield, will be offering plans on the exchange next year. The state's insurance regulator approved a whopping 76 percent average hike, as the state's top insurance regulator said the law was on "life support."

Experts have said that the rate hikes this year are essentially a market correction by insurers, which underpriced plans when the marketplace went online in 2014.

In addition, several programs created to help insurers mitigate major losses in the changes will expire next year.

The administration has pushed back against the spikes by pointing out that a majority of Obamacare customers will still get affordable coverage thanks to subsidies. Roughly 85 percent of Obamacare customers get some form of tax credit, and those credits increase alongside any premium hikes.

However, that doesn't apply to the roughly 15 percent who do not get premiums.

The administration has responded that those people can shop around to find a cheaper plan.

"In 2016, consumers could choose among an average of 10 plans per issuer," said Jonathan Gold, spokesman for the Department of Health and Human Services. "Prior to the Affordable Care Act, it was almost impossible to shop around for health insurance."

One expert said that the rate increases might be short-term pain, but long-term gain.

"While big premium increases are a problem right now for the marketplace, they will put insurers on much more solid financial footing next year," said Larry Levitt, senior vice president of the nonpartisan Kaiser Family Foundation.