After years of hearing they will face a fine for failing to have health coverage, that bill is finally coming due for millions of Americans this tax season.
The Obamacare penalty, which relates to lacking coverage in 2014, is spurring some of those people to sign up for insurance this year to avoid paying an even bigger fine next year. But not nearly every one of the estimated 6 million people subject to the penalty this season is taking advantage of that second chance.
"The penalty next year is ridiculous," said Shelby Robertson, a 24-year-old massage therapist, who was motivated to finally sign up for a health plan after having her taxes done recently by H&R Block.
Robertson knew about the fine for not having insurance last year when she had her taxes done. But she hadn't realized that for the 2014 tax season—the first ever for the Obamacare penalty—it would be the higher of $95 or 1 percent of her taxable household income.
When her return was completed, Robertson learned she'd have to pay $190 in Obamacare fines—quite a bit more than she had expected.
"My husband wasn't too happy," she said. "I wasn't pleased ... I thought it was kind of over the top. Why is it necessary to pay that?"
Still, that fine was manageable for Robertson, who hadn't believed she could afford insurance and "didn't feel like I need it," she said.
But the prospect of paying a larger fine in 2016—when it will be the higher of $325 per adult or 2 percent of household income—spurred her to action. Robertson said her tax preparer warned her she was looking at a fine of about $600 next year.
"I'd rather pay the smaller fine than the big, nasty one next year," she said.
Robertson signed up in late March for a health plan sold through the GoHealth Web brokerage, which has partnered with H&R Block to handle customers interested in enrolling in coverage to comply with the Obamacare mandate. After getting federal subsidies to offset the plan's cost, "I'll be paying $75 and some change per month." Her annual deductible is "really low," at just $300, she said.
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Brittany White, a 28-year-old actress in Los Angeles, is another person who is planning to sign up for a health plan this year after getting hit with the fine for last year.
"I was really worried" about the penalty, White said. "I did know I was going to owe," but, she added, "I had no idea what it was going to be."
After doing her return on TurboTax, White found out that she owed just $95—the low end of the fine.
"I was surprised," she said. "It was less than I expected."
White's decision to get insurance for this year has little or nothing to do with the penalty for next tax season. She said she didn't know what the penalty will be next year.
"I need to have insurance. It's something that I don't want to gamble with," White said.
She had signed up for a plan earlier this year, but dropped it after reading the fine print on the terms, and discovering "it was too good to be true." She plans to go to California's Obamacare exchange to look for a new plan.
Michael Mahoney, GoHealth's senior vice president of marketing, said the brokerage is getting plenty of calls from people like Robertson, who want to sign up for insurance "because they found out they're going to have to pay the penalty, and the penalty's going to increase."
Some are very surprised by the amount of money they owe for failing to have coverage last year. Others are surprised to find they owe a prorated penalty because they lost coverage during the course of the year due to losing a job, for example.
And, Mahoney said, "They're shocked by the large nature of the penalty" for 2015.
But even so, many people remain reluctant to sign up for insurance.
In Queens, New York, where Daniel Portillo prepares taxes for primarily lower-income people in the Rock & Hammer Tax Service mobile office, "a lot of people get the penalty," he said. Most owe the minimum, $95.
But when Portillo tells them they can avoid a bigger fine next year by signing up for an insurance plan with subsidies from the federal government, people often don't take his advice.
"They say they can't afford it, that the premiums are very heavy," Portillo said. Even when "they understand that they're only going to pay a portion of the premiums, they say it's unaffordable," he said.
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Last week, the Obama administration revealed that just 36,000 people in 36 states had signed up for health plans during an ongoing special enrollment period on HealthCare.gov open to those who only this year are learning they are subject to the penalty for failing to have coverage. Another 18,000 have signed up on California's exchange for its special enrollment season.
Those low numbers contrast dramatically with the nearly 11.7 million people who signed up for Obamacare plans nationally before the mid-February close of open enrollment.
Mark Steber, chief tax officer of Jackson Hewitt Tax Service, said there "is still a great deal of misinformation in the marketplace." Many people, Steber said, aren't aware of either the penalty or the special enrollment period being offered by HealthCare.gov and most of the state-run Obamacare exchanges.
A survey from Jackson Hewitt released in March found that 48 percent of adults believed the deadline for signing up for 2015 had expired, and another 27 percent said they "don't know" if the deadline had passed.
Jackson Hewitt hasn't seen a significant increase in the pace of enrollment among its customers responding to the special sign-up period, Steber said.
Brian Tap, a 47-year-old in Grand Junction, Colorado, knew about the penalty and knew about the subsidies, but he still chose not to buy insurance last year and this one.
Tap, who runs a graphics and sign business while his wife Diana operates a seasonings company, had avoided buying an Obamacare plan last year in part because "I wasn't confident about the security of the website."
He also doesn't like the Affordable Care Act and its mandate requiring nearly all Americans to have some form of health coverage. And he said he disapproves of the subsidies, saying, "I'm a free market kind of guy."
"This whole thing, I'm not happy with," Tap said. "I'm hoping that in a couple of years, it's going to be repealed."
Although he knew about the fine, he had heard on the news that it was going to be just $95. But when he prepared his taxes, he realized he would pay "much more than the $95 even though we don't make that much money."
When Tap spoke to CNBC, he was still amazed by the complexity of IRS Form 8965, which filers use for claiming any exemptions from the Obamacare penalty and for figuring out the penalty they owe for failing to have coverage. The portion of the form related to calculating the penalty has 14 separate lines for people to fill out.
"This form is crazy," Tap said. "It sort of blew my mind when I saw it."
While Tap said he expects he'll be able to figure out the correct penalty, he thinks that for other people who are accustomed to filling out a 1040EZ form by hand, the "mind-boggling" complexity of the new Obamacare penalty worksheet is "going to drive them nuts."
Even if he has a change of heart about signing up for health insurance after calculating his fine for this year, Tap is out of luck—Colorado is one of just three states not offering a special enrollment period. That means he and his wife likely will owe a bigger fine next year.