North Carolina Republican U.S. Sen. Richard Burr joins Oklahoma colleague Tom Coburn in writing a new National Review Online column warning of an impending “Obamatax.”

As we continue to review last week’s sweeping decision and its consequences for the American people, it is worth taking stock of Obamacare, perhaps now better named “Obamatax,” starting with a less-well-known $87 billion tax buried in the law that could force families to pay an extra $500 a year in premiums. The tax is described in the law as an “annual fee” levied on insurance companies. Actually, the fee is really just a tax by another name — the health-insurance tax, or HIT, in this case. Tax economists — inside and outside government — agree that the bulk of new fees and taxes are simply passed by businesses on to their customers, which, as we’ll see, in this case are small employers and families. Unless this tax is repealed, it will soon force families and small businesses to pay even more for their coverage.

Here’s how it works: The law taxes health plans based on their net premiums. Bigger health plans pay more, small plans pay less — or at least that’s how it sounds. But the law’s definition of a “health plan” excludes companies that self-insure. This means that Fortune 500 companies and other large firms who self-insure dodge this tax, leaving the brunt of the tax to fall on small businesses and families.

As the Joint Committee on Taxation explained, “a very large portion of the insurance industry fee [would] be passed forward to purchasers of insurance in the form of higher premiums.” According to analysis by the actuarial firm Oliver Wyman, this tax could increase premiums for an average family in the small-group market by $6,800 over the decade that starts in 2014.