The Literature Library.

OBBBA (P.L. 119-21), signed July 4, 2025 with most provisions effective January 1, 2026, restructures four federal affordable housing finance tools at once. The 12% LIHTC per-capita boost is permanent, which translates the 2026 multiplier into $3.416 per resident (vs. $3.05 pre-boost) and the small-state floor into $3,953,600 (Rev. Proc. 2025-32). The bond financed-by test for 4% LIHTC drops from 50% to 25% for properties placed in service after Dec 31, 2025 (with a separate ≥5% of aggregate basis requirement for bonds issued after that date) — Novogradac estimates this alone could unlock material additional 4% deal capacity over the next decade.

NMTC is now permanent at a $5B annual cap, removing the cyclical reauthorization risk that had complicated multi-year fund planning. OZ is made permanent through a new decennial designation cycle (OZ 2.0 designations effective Jan 1, 2027), with a new Rural OZ category; original 2028 designations are not extended — both maps run concurrently through Dec 31, 2028. OBBBA also terminates Section 45L (for homes acquired after June 30, 2026) and Section 179D (for property the construction of which begins after June 30, 2026), and restores 100% bonus depreciation under IRC §168(k) for property placed in service after January 19, 2025.

For practitioners: re-underwrite any 2026–2030 LIHTC pipeline against the new state allocation envelopes, and re-evaluate any deal that was sized to the old 50% bond test. The CRS report on OBBBA housing provisions is the recommended starting overview.

Section 42 is the foundational LIHTC statute, enacted as part of the Tax Reform Act of 1986. It defines who can claim the credit (owner of a qualified low-income building), how much credit is generated (applicable percentage × qualified basis, over a 10-year credit period), the set-aside elections (40/60, 20/50, average-income), the 15-year compliance period and the extended-use period, and the recapture mechanics.

Practitioners should focus on §42(d) (eligible basis), §42(g) (set-asides and income limits), §42(h) (allocation, including per-capita and credit ceiling), §42(i) (definitions and special rules), and §42(j) (recapture). The 4% credit is governed by §42(b)(3) in conjunction with the PAB financing rules of §142(d). The OBBBA 12% permanent boost amends the §42(h)(3)(C) per-capita language; the 4% bond financed-by test sits in §42(h)(4) with cross-references to §146 and §142.

§45D (NMTC): A 39% federal credit claimed over 7 years for qualified equity investments in CDEs that fund low-income community businesses. CDFI Fund administered. Permanent at $5B/yr under OBBBA.

§47 (HTC): A 20% federal credit for the qualified rehabilitation expenditures of certified historic structures. Claimed ratably over 5 years post-TCJA. Frequently twinned with 4% LIHTC.

§§1400Z-1 and 1400Z-2 (OZ): §1400Z-1 governs zone designation; §1400Z-2 provides the capital-gains deferral (originally through Dec 31, 2026), step-up basis benefits, and 10-year hold appreciation exclusion. OBBBA made the OZ regime permanent and added a Rural OZ category.

HERA's most enduring LIHTC provision is the "HERA Special" hold-harmless treatment for AMI-based rent and income limits at LIHTC properties: limits cannot decrease year-over-year for properties placed in service before relevant HUD AMI updates. This matters most in metro areas where HUD AMI estimates have dropped (rare but real). HERA also created the Housing Trust Fund (HTF), the first new federal affordable housing funding stream since the early 1990s.

HERA established the FHFA, placed Fannie Mae and Freddie Mac into conservatorship, and provides the statutory framework that still governs the GSEs' affordable housing duty-to-serve obligations.

HOTMA touches a wide set of HUD-administered programs — HCV, Project-Based Vouchers, PHA capital fund, mortgage insurance — with the most operationally consequential provisions being income and asset rules. The income provisions standardize and somewhat simplify how PHAs and owners calculate household income and assets, including new safe harbors for de minimis assets and updated treatment of retirement accounts. HOTMA also tightened over-income provisions for public housing tenants.

Implementation has been delayed and rolled out in tranches; HUD-issued PIH Notices and CPD Notices over 2023–2026 are the operational reading.

Rev. Proc. 2025-32 is the IRS's annual inflation adjustment for housing-related tax provisions. The 2026 LIHTC per-capita of $3.416 reflects OBBBA's permanent 12% boost layered on top of the otherwise inflation-adjusted figure. The PAB per-capita of $135 was corrected from a prior erroneously circulated $130 figure — if you see $130 anywhere, the source is out of date.

Required reading every fall for QAP analysts, state HFA staff, and bond counsel. Pair with Notice 2024-XX-series for any updated guidance on the income-averaging rules or specific compliance items.

The 24 CFR parts are where statute meets practice. Part 92 (HOME) defines participating jurisdictions, match requirements, eligible activities, affordability periods, and underwriting. Part 93 (HTF) sets the ≤30% AMI targeting, set-asides, and PJ obligations. Part 570 (CDBG) governs the entitlement and state allocations, eligible activities, and national objectives. Parts 982/983 (HCV/PBV) define voucher administration, project-based attachments, rent reasonableness, and HAP contracts.

Read alongside the relevant HUD Notices (CPD for HOME/HTF/CDBG; PIH for HCV/PBV) for current operational guidance, since the regs lag policy updates by months or years.

Part 1291 covers the structure of the FHLB Affordable Housing Program: how each district sets aside 10% of net income for AHP, the General Fund competitive application, the homeownership and rental set-asides, scoring criteria categories, monitoring, and recapture. The companion Implementation Plan from each FHLB applies the rule to that district's specific scoring matrix and deadlines.

If you're writing an AHP application, read your district's Implementation Plan first — the federal regulation only sets the categories; the local plan decides the weights and thresholds.

The 2026 edition centers on the post-OBBBA supply outlook and the trajectory of rent-burdened households through 2030. Headline chapters cover homeownership accessibility, rental affordability, the affordable supply gap, federal program scale (LIHTC, HCV, PBV), and demographic shifts.

Cite when you need a defensible single-source data point on national-scale affordability. Pair with HUD's American Housing Survey for sub-MSA detail.

The Gap measures — using HUD ACS-PUMS-based methodology — how many affordable, available rental units exist per 100 ELI renter households. The 2026 edition incorporates post-OBBBA supply projections for the first time and continues to show a national shortfall of roughly 7M units, with the deepest gaps in CA, NV, OR, AZ, FL, and TX metros.

Most useful for: AHP applications and QAP letters of support arguing the case for ELI-targeted deals; press and advocacy framing.

Out of Reach computes the housing wage required to afford a HUD Fair Market Rent (FMR) two-bedroom unit at 30% of household income, for each U.S. metro area. Includes the gap vs. minimum wage and median renter wage. Released annually around the Memorial Day window.

Use for community development arguments, fair-housing analysis context, and stakeholder communications. The methodology is transparent and widely cited.

Urban's HFPC publishes regular briefs and longer studies on the operation, distribution, and outcomes of federal housing programs. The HFPC's LIHTC tenant data work and its post-2026 program scale modeling are standard practitioner references.

Furman's strength is detailed, market-level analysis of zoning, rent-regulated stock, neighborhood change, and the affordable housing pipeline. The annual State of New York City's Housing & Neighborhoods report is the deepest single resource on NYC's housing market.

Terner publishes policy briefs and longer studies on California housing market dynamics, the state's LIHTC and gap-financing programs, and the operational impacts of state housing legislation (SB 9, AB 1287, SB 423, etc.). Particularly useful when your work touches California or when state-policy comparisons matter.

Cityscape is HUD's in-house peer-reviewed journal. Symposium issues cover specific themes (vouchers, LIHTC, fair housing, homelessness) with three to six full-length research articles each. Open access, well-cited, often the first place HUD-funded research appears.

CRS reports are written for Congressional offices — they have to be technically accurate, current, and balanced. That makes them an underused practitioner resource. Look for: "An Introduction to the Low-Income Housing Tax Credit" (RS22389), "The HOME Investment Partnerships Program" (R40118), "The Housing Trust Fund" (R40781), "Opportunity Zones" (R45152). Every major OBBBA-touched program now has an updated CRS report.

NCSHA's Factbook compiles state-level data on LIHTC allocations, bond issuances, gap-financing program activity, and HFA-administered single-family bond programs. The full Factbook is member-only; NCSHA publishes summary statistics openly that are widely cited in policy debates and in annual industry overviews.

The Journal of Tax Credits is the trade publication closest to practitioner workflow. Each issue carries regulatory updates, deal-level case studies, syndicator pricing benchmarks, and OBBBA-era impact analyses. Novogradac's blog and webinar series complement the Journal and often surface analysis ahead of the print release.

If you work LIHTC, NMTC, or HTC deals professionally, the subscription pays for itself within a year.

Tax Credit Advisor (TCA) covers similar ground to the Novogradac Journal but with NH&RA's practitioner-association vantage point. Strong coverage of historic tax credit deal structures, renewable+affordable pairings, and federal regulatory developments. NH&RA also runs the leading mid-year and fall HTC/NMTC conferences whose proceedings often appear in TCA.

AHF's coverage is broader and lighter than Novogradac/TCA, with strong access to operating developers and syndicators for deal-level interviews and project profiles. Useful for staying current on who's closing what kind of deals and for industry awards/recognition coverage. Free registration unlocks the full archive.

HUD's Notice series is where most practitioner-relevant rule guidance lands. CPD Notices govern day-to-day operation of formula-grant programs; PIH Notices govern HCV/PBV/RAD/public housing; Mortgagee Letters govern FHA mortgage insurance. Subscribe to HUD's email list for the series most relevant to your work; the operational impact is often higher than the underlying regulations.

The IRB is the official weekly compilation of IRS guidance; the Federal Register is the daily publication of federal regulations, NOFAs, and other formal federal actions. Both offer email/RSS subscriptions. If you work tax credits, the IRB is required reading. If you work HUD/USDA/FHFA programs, the Federal Register is.

Rothstein argues that twentieth-century U.S. residential segregation was a product of explicit federal and state policy, not just private discrimination. Key chapters cover FHA redlining, restrictive covenants, urban renewal, and public housing siting. Read it before any AFFH or fair-housing argument in a QAP application or policy filing.

Gruber is the standard graduate-level public finance text. The chapters on tax expenditures, distributional analysis, and behavioral responses to tax incentives are the academic counterpart to practitioner LIHTC work — useful when you need to write about a program's economic logic rather than its mechanics. Pair with Burman & Slemrod for richer tax-policy depth.