Section 601(a) states four purposes, and they are worth reading because they explain why TANF funds things that are not cash. The purposes are to provide assistance so children can be cared for at home or with relatives, to end dependence on government benefits through job preparation, work and marriage, to prevent out-of-wedlock pregnancies, and to encourage two-parent families. Only the first is about cash. Section 604(a)(1) then lets a state use its grant "in any manner that is reasonably calculated to accomplish the purpose of this part", a phrase broad enough that states fund child care, transport, short-term emergency payments and administrative services out of the same pot. The statute names one such use explicitly, permitting a state to spend the grant "including to provide low income households with assistance in meeting home heating and cooling costs", which is why TANF and LIHEAP show up together. Not more than 15 percent of the grant may go to administrative purposes, under 604(b)(1).
The grant itself is a fixed appropriation, and the amendment history of the subsection shows how fixed. Section 603(a)(1)(C) appropriates $16,566,542,000 "for grants under this paragraph", and every amendment to that subparagraph has moved only the window it covers, never the dollar figure: "2003" became "fiscal year 2012" in 2012, and "fiscal year 2012" became "each of fiscal years 2017 and 2018" in 2017, which is where the codified text still stands. Each state's State Family Assistance Grant is a historical share of that total, computed under 603(a)(1)(B) from what the state was paid for fiscal year 2002. A fixed nominal appropriation behaves very differently from an open-ended match. It does not grow when a state's caseload grows, and it buys less each year that prices rise. That is a design consequence rather than an oversight, and it is the mechanism to look at before asking why a state's grant amounts have moved the way they have.
The 60-month limit at 42 U.S.C. 608(a)(7) is the rule most often misdescribed. It is a restriction on the state, not a clock the recipient owns. Paragraph (A) prohibits a state from using any part of its grant to assist a family that includes an adult who has already received federally funded assistance for 60 months, "whether or not consecutive". Three refinements follow. Paragraph (B) disregards months in which the individual was a minor child who was not a head of household or married to one. Paragraph (C)(i) lets a state exempt a family for hardship or where the family includes someone who has been battered or subjected to extreme cruelty, and (C)(ii) caps those exemptions at an average of 20 percent of the state's caseload. Because (A) restricts only assistance "attributable to funds provided by the Federal Government", the limit constrains federal dollars rather than state ones. And because 601(b) creates no entitlement in the first place, nothing requires a state to offer the full 60 months; a state is free to adopt a shorter one.
Work requirements operate on the state first and the family second. Section 607(a) requires each state to achieve a minimum work participation rate of 50 percent of all families receiving assistance from fiscal year 2002 onward, and 90 percent of two-parent families from fiscal year 1999 onward. Section 607(c)(1)(A) then defines when a recipient counts toward that rate. From fiscal year 2000 onward a recipient must participate in work activities for an average of at least 30 hours a week, of which at least 20 must come from the core activities listed in 607(d). A single parent caring for a child under six is deemed to be meeting the requirement at 20 hours a week under 607(c)(2)(B), and for a two-parent family the combined requirement rises to 35 hours, or 55 hours where the family receives federally funded child care and no adult is disabled or caring for a severely disabled child. States face financial penalties for missing the rates, which is why state eligibility rules are built around who will count in the numerator.
Receiving TANF also functions as a key that opens other doors. A household in which every member receives TANF is categorically eligible for SNAP, receipt of TANF satisfies WIC's income test, and TANF receipt is one of the categorical routes into LIHEAP. Losing TANF can therefore ripple through several programs at once, which is worth knowing before a time limit hits.