Roughly 3.2 million people are paying less than $100 per month for health insurance thanks to subsidies on ObamaCare's federally run exchanges, the administration said in a report released Wednesday.
That group of enrollees represents 69 percent of those who signed up with financial assistance on the federal marketplace. Forty-six percent of those people are paying less than $50 per month, officials said.
"The bottom line is that tax credits matter," senior HHS officials told reporters, noting that subsidies reduced the cost of the average premium from $346 to $82.
"They are working as intended to make premiums more affordable … and we expect the market to look very similar [in 2015]."
The net cost of ObamaCare's subsidies is a sticking point in debates over the healthcare law.
While supporters say the tax credits are necessary to help lower-income people afford coverage, opponents argue they will prove too expensive and ultimately weigh down the federal budget.
The report also arrives as the administration awaits news on 2015 premium prices.
State regulators are in the process of approving proposed rate increases, which have been largely modest so far, and the administration is continuing an effort to keep the headlines positive.
The administration also sought to play up news that more insurers are joining the exchanges in their second year, arguing the trend will help lower prices.
In 10 states where data is available, at least 27 insurers have indicated they will offer plans on the marketplaces for the first time in 2015.
Adding one insurer to an exchange is associated with a 4 percent drop in the benchmark premium price, the HHS report stated. In total, consumers on the exchange an average choice of five insurers and 47 plans this year.
"It seems likely that with more issuers, consumers will have greater choice [next year] and the benchmark plan will become more affordable," senior HHS officials said.
ObamaCare opponents criticized the data as misleading and incomplete.
"The report focuses on averages, a way to highlight seemingly good news without telling the full story," said American Action Forum President Douglas Holtz-Eakin in a statement.
"The report does not demonstrate that families had more choices or that premiums are lower in the past. It does demonstrate that consumers avoid 76 percent of premiums because federal spending subsidizes the cost."