(CNN) The cost of "Medicare for All" was front and center at the 2020 Democratic presidential debate yet again.
Multiple estimates have pegged the cost of Medicare for All at more than $30 trillion over a decade -- a big chunk of change for taxpayers to cover.
But it's important to know exactly what that figure means. It doesn't reflect an increase in total US spending on health care. It's how much federal spending would rise because the federal government would cover nearly all medical care. This would require a big hike in taxes.
On the flip side, however, other spending would go down. The new federal health insurance system would replace what states spend on programs like Medicaid and employers would no longer be on the hook for covering their share of worker premiums. Individuals would no longer have to pay premiums, deductibles and other out-of-pocket costs.
The debate over Medicare for All, however, isn't only about taxes or costs -- it's about whether to remake the nation's health insurance system, shifting the bulk of spending to the public sector, rather than leaving the choices up to individuals and employers.
The sparring was evident in Tuesday's Democratic debate hosted by CNN and The New York Times. Massachusetts Sen. Elizabeth Warren was pressed to explain how she would pay for Medicare for All without raising taxes on the middle class -- something Minnesota Sen. Amy Klobuchar called "a pipe dream." Warren responded that the rich and big companies would cover the tab, but she danced around the impact on the middle class, saying these families would not see an increase in "costs."
"Costs will go up for the wealthy, they will go up for big corporations and for middle class families they will go down," said Warren, who has not released her own health care plan, instead voicing support for Vermont Sen. Bernie Sanders' Medicare for All. "I will not sign a bill into law that does not lower costs for middle class families."
Sanders, on the other hand, acknowledges that he would raise taxes on the middle class -- he's floated a 4% levy on employees, exempting the first $29,000 in income for a family of four, as an option. But he argues that many would still come out ahead because they would no longer have to pay for private insurance or for medical care.
Since private insurance would essentially disappear, Americans would no longer have to pay annual premiums, which cost a family about $6,000, on average, according to the Kaiser Family Foundation. And they would no longer have to pay deductibles or copays.
The shift would also affect employers and states.
Companies would no longer be on the hook for annual premiums, which cost employers more than $14,000 for a family policy, on average. States would also see their outlays go down since they would no longer pay for medical care for those on Medicaid or the Children's Health Insurance Program (CHIP) or for uncompensated care at hospitals.
Sanders has suggested that Medicare for All would end up reducing the amount the country spends on health care, which experts say isn't true -- though individual households might end up coming out ahead.
The Sanders campaign argues that under a single payer system, the federal government would have the leverage to lower spending. A spokesman pointed to several studies that say overall spending would go down under Medicare for All.
But a new Urban Institute study shows that the nation's overall health care spending is expected to rise roughly $7 trillion to $59 trillion over a decade if Medicare for All goes into effect, said Linda Blumberg, institute fellow at the institute's Health Policy Center. The increase would be $720 billion for 2020 alone if the policy were enacted.
That's because more people would be insured, more benefits would be covered and more medical services would be used since there'd be no cost for care.
"You will in total spend more as a nation on health care from adding all the bells and whistles that are associated with these kinds of proposals," said Blumberg.
The latest Urban report, released Wednesday, pegs a Medicare for All-type plan as raising federal spending by $34 trillion over a decade.
Looking at the impact in 2020 alone, federal spending would skyrocket to $4.1 trillion, an increase of $2.8 trillion, according to Urban. But state spending would drop to $43 billion, a decline of $260 billion.
Employers, meanwhile, would save the entire $955 billion they would have shelled out on health care.
And households would see their spending plummet by nearly $887 billion, leaving them with a tab of roughly $45 billion to pay for institutional long-term care.
But what matters is how much federal spending increases since that determines how much the government needs to raise in taxes, said Charles Blahous, senior research strategist at Mercatus, noting that his 2018 study found the federal tab could be as high as $39 trillion depending on drug costs and provider payment rates.