“Under current law, the payroll tax that funds Social Security is capped so that, for this year, only the first $168,600 in earnings are subject to it.
Raising that cap—or eliminating it—is frequently discussed as one possible solution to Social Security’s approaching insolvency. That seems to be the idea that Biden was gesturing towards in his speech.
On its face, this isn’t necessarily the worst idea. The cap is completely arbitrary, so there’s no principled reason why all earnings shouldn’t be treated equally. And there’s no doubt that raising the cap would generate more revenue to help keep Social Security afloat. The Congressional Budget Office estimates that applying payroll taxes to higher income levels could raise $1 trillion in revenues over a 10-year period (though the amount of revenue would depend on how the cap was altered, and whether benefits increased as well).”
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“raising or eliminating the payroll tax gap doesn’t come close to solving the long-term Social Security shortfall. It might generate $1 trillion over 10 years, which is a lot of money, but it doesn’t come close to the $2.8 trillion deficit the program is expected to run over the next decade.
“Eliminating the tax cap would either raise benefits as well (reducing the proposals’ savings), or—if the accompanying benefits are canceled—turn Social Security into a true welfare program by delinking contributions and benefits,” writes Brian Riedl, a senior fellow at the Manhattan Institute and former Senate budget staffer, in a recent piece debunking some common myths about Social Security reform. “Moreover, eliminating the cap would not bring permanent solvency or avert the need for benefit changes….The system would return to deficits by 2029. Lawmakers would still need to reform benefit levels and the eligibility age.””