ObamaCare premiums will soar by an average of 25 percent in 39 states next year, the Obama administration said Monday, giving new ammunition to critics who warn of a “death spiral” in the national health insurance program.

In some states, the premium increases are staggering.

In Arizona, unsubsidized rates for a 27-year-old buying a benchmark “second-lowest-cost silver plan” were scheduled to jump by 116 percent, from $196 to $422 a month, according to the administration. Oklahoma consumers face the next-largest increase — 69 percent.

The government also said the total number of insurers would drop from 232 to 167 in 2017, a loss of 28 percent.

One in five consumers will have to make do with a single insurer in their market.

The increases in states that use the federal healthcare.gov exchange are sure to become an issue in the final two weeks of the presidential race.

Even before the numbers were released, critics were warning that insurance markets created by Obama’s 2010 Affordable Care Act were on the verge of collapsing into a “death spiral.”

Sign-up season starts Nov. 1, a week before the elections for president and Congress.

The average increase for New Yorkers buying individual policies was previously estimated at 16.6 percent. In 2016, premiums rose only 7.2 percent.

“Consumers will be faced this year with not only big premium increases but also with a declining number of insurers participating, and that will lead to a tumultuous open enrollment period,” said the Kaiser Family Foundation’s Larry Levitt.

Health and Human Services spokesman Kevin Griffis said, “Headline rates are generally rising faster than in previous years.”

But, in a briefing with reporters, Griffis remained optimistic.

“We think [consumers] will ultimately be surprised by the affordability of the premiums, because the tax credits track with the increases in premiums,” he said.

The vast majority of the more than 10 million customers who purchase policies through healthcare.gov and its state-run counterparts receive generous financial assistance.

“Enrollment is concentrated among very low-income individuals who receive significant government subsidies to reduce premiums and cost-sharing,” said Caroline Pearson of the consulting firm Avalere Health.

But an estimated 5 million to 7 million people are either not eligible for the income-based assistance, or they buy individual policies outside of the health law’s markets, where the subsidies are not available.

Hillary Clinton and Donald Trump have staked out starkly different positions on the national health coverage law.

Clinton has said she wants to keep ObamaCare while making improvements. Trump has proposed a full repeal and a new, unspecified health care plan.

“This is all very predictable — yet so very contrary to what Democrats promised when they rammed this thing through. It costs too much and it’s not working the way they promised it would,” said Don Stewart, a spokesman for Senate Majority Leader Mitch McConnell (R-Ky.).

“Democrats have a recycled idea to fix the problems that even they grudgingly admit are plaguing families.

“Their answer? More ObamaCare and more government.”