42 U.S.C. § 413 — Quarter and quarter of coverage

(a) Definitions. (1) "Quarter" and "calendar quarter" mean a three-calendar-month period ending March 31, June 30, September 30, or December 31. (2)(A) "Quarter of coverage" means (i) for calendar years before 1978, subject to subparagraph (B), a quarter in which a person was paid $50 or more in wages (except farm-labor wages paid after 1954), or was credited (under section 412) with $100 or more of self-employment income; and (ii) for calendar years after 1977, subject to subparagraph (B), each portion of a person's yearly wages plus credited self-employment income that equals the amount required for a quarter of coverage that year (set under subsection (d)) — assigned to a specific calendar quarter only when necessary to meet the insured-status rules in section 414(a) or (b), the rules for a benefit computation or recomputation, or section 416(i)(3), for someone who has turned 62, died, or become disabled. (B) Despite subparagraph (A): (i) no quarter after the one in which a person dies counts as a quarter of coverage, and no quarter within a period of disability counts except the first and last such quarter; (ii) if a person's yearly wages reach a set ceiling — which rises over time, from $3,000 before 1951 up to the "contribution and benefit base" set under section 430 for years after 1974 — every quarter of that year counts as a quarter of coverage; (iii) the same rule applies, using matching thresholds, when self-employment income plus wages for a tax year reach the ceiling; (iv) special step-up rules apply to farm-labor wages paid in a calendar year after 1954 and before 1978 — depending on whether such wages reach $100, $200, $300, or $400, the last one, two, three, or all four quarters of that year (that are not already quarters of coverage) become quarters of coverage; (v) no quarter can be counted as a quarter of coverage before that quarter begins; (vi) no more than one quarter of coverage may be credited to any single calendar quarter; and (vii) no more than four quarters of coverage may be credited to any calendar year after 1977. If applying clause (iv)'s farm-wage rule still leaves someone short of the insured-status or benefit-computation requirements, but assigning those quarters of coverage to different quarters in the same year would satisfy them, the law allows that reassignment — solely to determine whether those requirements are met. And for a person who did not die before January 1, 1955 and who turned 62 (if a woman), turned 65 (if a man), or died before July 1, 1957, if they fall short of the insured-status requirement in section 414(a)(3) only because of how their first year of covered wages was counted, they (or their survivors) may apply, with satisfactory proof, to have that year's quarters of coverage figured based on when the wages were earned rather than when they were paid — though wages recounted this way are not used again to figure quarters of coverage for later years. (b) Crediting of wages paid in 1937: For wages paid in the six-month periods starting January 1, 1937 or July 1, 1937: (A) if at least $100 was paid in a period, half of that total is treated as paid in each of that period's two calendar quarters; and (B) if less than $100 was paid in a period, the full amount is treated as paid in the later quarter of that period — except that if the person turned 65 during that period, all wages paid in it are treated as paid before they turned 65. (c) Alternative method for determining quarters of coverage with respect to wages in period from 1937 to 1950: For sections 414(a) and 415(d), a person is treated as having one quarter of coverage for every $400 of their total pre-1951 wages (as defined in section 415(d)(1)(C)) — except where that method, combined with quarters of coverage earned from wages and self-employment income after 1950, still does not make the person "fully insured." (d) Amount required for a quarter of coverage. (1) The amount of wages and self-employment income someone needs to be credited with a quarter of coverage under subsection (a)(2)(A)(ii) is $250 for calendar year 1978, and whatever paragraph (2) determines for later years. (2) On or before November 1 of 1978 and every year after, the Commissioner of Social Security must determine and publish in the Federal Register the amount of wages and self-employment income needed for a quarter of coverage in the next calendar year. That amount is the larger of (A) the amount already in effect for the year the determination is made, or (B) the 1978 amount from paragraph (1) multiplied by the ratio of the national average wage index (as defined in section 409(k)(1)) for the year before the determination to that index for 1976 — with the result rounded up to the next $10 if it is a multiple of $5 but not $10, and rounded to the nearest $10 otherwise.