Makes comprehensive changes in Social Security coverage, financing, and benefit structure. Following are major provisions of the legislation which incorporate the recommendations of the National Commission on Social Security Reform: Covers under Social Security the following groups: (1) Federal employees hired on or after January 1, 1984;
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3) Employees With No Social Security Coverage The final category of workers includes those who are not subject to any voluntary or mandatory social security coverage at all. This can only occur where the workers are covered by a qualifying public retirement system. Employers of these workers will not withhold social security taxes or show any 'social security wages' on Form W-2.
I must have been thinking of Medicare, since Medicare switched to "no opt-out" in the 1980s. From page 5-16:
Prior to April 1, 1986, the only way for state and local government employees to be covered for Medicare was by voluntary Section 218 Agreements between the states and the Federal government. This changed with the enactment of the Consolidated Omnibus Budget Reconciliation Act (COBRA) of 1985, which mandated that almost all state and local employees hired or rehired after March 31, 1986 must be covered for Medicare, and pay Medicare taxes regardless of their membership in a retirement system.
I still think opt-out is impossible for private sector workers at least for now. There are, however, a few specific types of income which are exempt; gory details in a table starting on page 30 of http://www.irs.gov/pub/irs-pdf/p15.pdf.
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