Looking Under the Hood of the Cadillac Tax.

One effect of the Affordable Care Act's "Cadillac tax" (now delayed until 2020) is to undo part of the existing federal tax preference for employer-sponsored insurance. The specific features of this tax on high-cost health plans--notably, the inclusion of tax-favored savings vehicles such as health savings accounts (HSAs) in the formula for determining who is subject to the tax--are designed primarily to maximize revenue and minimize coverage disruptions, not to reduce health spending. Thus, at least initially, these savings accounts, rather than enrollee cost-sharing or other plan features, are likely to be affected most by the tax as employers act to limit their HSA contributions. Because high earners are the ones benefiting most from tax-preferred accounts, the high-cost plan tax will probably be more progressive than prior analyses have suggested, while having only a modest impact on total health spending.