"First four years" is four separate tests, and three of them get dropped by most summaries. Section 25A(b)(2) sets them out individually. The credit cannot be elected for a student if an election was already in effect for that student for any four prior taxable years, whether the earlier claims were made by this taxpayer or anyone else. The student must be an eligible student for at least one academic period beginning during the year. The student must not have completed the first four years of postsecondary education before the year began. And the student must not have a federal or state felony conviction for possession or distribution of a controlled substance. The practical consequence of separating the first and third tests is that a fifth-year senior who has not yet completed four years of study can still qualify if the credit has been claimed fewer than four times, while a student who finished a degree in three years cannot claim it in a fourth.
Eligible student is a defined term with an enrolment floor. Section 25A(b)(3) requires the student to meet the aid-eligibility requirements of section 484(a)(1) of the Higher Education Act and to be carrying at least half the normal full-time workload for their course of study. This is the credit's sharpest boundary against its sibling: a part-time student taking one course is out, and that is exactly the reader the Lifetime Learning Credit exists for.
Two rules that the two education credits share, stated once here. They share a single income phase-out, at section 25A(d)(1): the credit is reduced ratably as modified adjusted gross income runs from $80,000 to $90,000, or from $160,000 to $180,000 on a joint return, and is gone above the top of the range. Those figures are statutory and are not adjusted for inflation. Section 25A(h), which used to index the Lifetime Learning Credit's thresholds separately, was repealed at the end of 2020, and the two credits have shared one phase-out since. They also share a flat bar at section 25A(g)(6): no credit at all for a married taxpayer who does not file a joint return, at any income level.
The 2025 tax law tightened the identification requirement in a way that removes eligibility from real filers. Section 70606 of that Act rewrote section 25A(g)(1) to require a Social Security number rather than any taxpayer identification number, both for the taxpayer and, where the student is someone else, for that person. The change applies to tax years beginning after December 31, 2025, so it first bites on returns for 2026. A filer using an individual taxpayer identification number who could claim this credit for 2025 cannot for 2026. Explainers written before mid-2025 say "TIN". Separately, and unique to this credit, the return must carry the employer identification number of the institution.
The refundable 40 percent has an exception aimed at the student most likely to try to use it. Section 25A(i) switches refundability off for a child to whom the kiddie tax rules of section 1(g) apply, which is a substantial share of undergraduates claiming the credit on their own return. It also computes the 40 percent after the income phase-out has been applied, so a partially phased-out credit has a proportionately smaller refundable piece.
Scholarships come off first, before anything else is computed. Section 25A(g)(2) reduces qualifying expenses by tax-free scholarships, veterans' educational assistance and similar excluded payments, and it does so before the credit percentages and before the phase-out. A student whose tuition is fully covered by a scholarship has no qualifying expenses left, however large the tuition bill looked. And where a dependent's expenses are involved, section 25A(g)(3) treats them as paid by the taxpayer claiming the dependent and denies the credit to the dependent, so the credit follows the exemption claim rather than the person who wrote the cheque.