Percentage-of-completion rules for homebuilders under §70430

The One Big Beautiful Bill Act gives residential builders a new reason to review how long-term construction contracts are reported for tax purposes. Section 70430 of Public Law 119-21 amends Internal Revenue Code Section 460 by expanding the exception from mandatory percentage-of-completion accounting from home construction contracts to residential construction contracts.

For contractors, developers, and tax advisors serving the residential building market, the change is not just a technical wording update. Construction accounting concepts such as the long-term contract and the completed contract method now apply to a wider range of residential projects. The rule affects when contract income is reported, whether the completed contract method is available, and how cash tax estimates are planned before a project is signed.

The practical takeaway is straightforward. More residential construction contracts may now sit outside the mandatory percentage-of-completion method under Section 460. The benefit is usually timing, not permanent tax elimination. A builder may defer income recognition to a later year if the contract and accounting method support that treatment, but the income must still be reported when the method requires it.

This article explains what Section 70430 changed, how residential construction contracts differ from home construction contracts, why the new 3-year reference matters, and what builders should document before relying on the expanded exception.

How Section 70430 expands the Section 460 exception

Section 460 generally requires taxable income from a long-term contract to be determined under the percentage-of-completion method. A long-term contract is a contract for manufacturing, building, installation, or construction of property that is not completed within the taxable year in which the contract is entered into.

Before OBBBA, Section 460(e) excluded certain contracts from this framework. The most important construction exception covered home construction contracts, which generally involved buildings with four or fewer dwelling units, with at least 80 percent of the estimated total contract costs attributable to those dwelling units and related on-site improvements.

Section 70430 expands that exception. It replaces the home construction contract reference in Section 460(e)(1) with a residential construction contract, and adds a parallel 3-year reference for residential construction contracts that are not home construction contracts.

That broader language matters for residential projects that do not look like traditional single-family home construction. Multifamily buildings, apartment projects, condominium developments, student housing, senior housing, and other residential-unit projects may now warrant a fresh Section 460 review if structured as qualifying residential construction contracts.

The effective date is important. Section 70430 applies to contracts entered into in taxable years beginning after July 4, 2025, the enactment date of Public Law 119-21. For calendar-year taxpayers, that generally means contracts entered into in 2026 and later.

Section 70430(b) also updates Section 56(a)(3) to provide residential construction contracts with parallel treatment for alternative minimum tax purposes, thereby reducing AMT exposure for high-income builder-owners.

Why percentage-of-completion accounting matters for builders

The percentage-of-completion method recognizes contract income as work progresses rather than waiting until the project is complete. The method is designed to prevent taxpayers from deferring income on long-term projects for too long. IRS Publication 538 remains the operational reference for accounting periods and methods that interact with Section 460.

For a simple illustration, assume a residential contractor signs a $10 million contract with expected costs of $8 million and expected gross profit of $2 million. If the project is 40 percent complete at year-end, percentage-of-completion accounting may require the contractor to recognize roughly 40 percent of the expected profit, or $800,000, before the project is finished.

That can create cash-flow pressure. Residential builders often pay for labor, materials, permits, subcontractors, insurance, equipment, and financing well before the final sale or project closes. If taxable income accelerates faster than project cash, the tax bill can arrive while capital is still tied up in the job.

The expanded residential construction exception can reduce that timing mismatch when another permissible accounting method applies. The completed contract method, for example, generally recognizes contract revenue and costs when the contract is completed. That does not erase profit. It changes the year in which the profit is recognized.

How residential and home construction contracts differ under Section 460

The distinction between home construction contracts and residential construction contracts is the center of the OBBBA change.

A home construction contract under Section 460 applies to buildings containing four or fewer dwelling units, plus directly related on-site improvements. Each townhouse or rowhouse is treated as a separate building for this purpose. This definition worked well for many single-family and small residential projects, but it did not fit every residential development.

A residential construction contract keeps the basic dwelling-unit concept but removes the four-or-fewer dwelling-unit limitation. That broader wording can bring larger residential projects into the Section 460(e) exception, assuming the contract otherwise meets the statutory definition. Many builders operating through S Corporations, Partnerships, or C Corporations should review whether method-change opportunities align with their chosen entity structure.

This is where builders need to be careful. A project labeled residential in a marketing deck is not enough. The analysis should start with the actual contract, the work being performed, the expected cost allocation, the property type, and whether the contract is for building, construction, reconstruction, rehabilitation, installation of integral components, or improvements to real property.

Mixed-use projects require extra attention. A building with residential units, ground-floor retail, parking, and shared infrastructure may require a closer cost and contract analysis to determine whether the contract qualifies as residential construction and whether costs need to be allocated.

Why the new 3-year rule matters for larger residential projects

Section 70430 also adds a special 3-year reference for residential construction contracts that are not home construction contracts. In applying the relevant Section 460(e)(1)(B) requirements to those contracts, the statute substitutes a 3-year term for a 2-year term.

That detail matters because larger residential projects often take longer than smaller home construction jobs. A multifamily building or condominium project may reasonably take more than two years from the contract's commencement, even when it remains clearly residential in nature.

The 3-year reference does not mean every 3-year residential project automatically produces the best tax result. It affects how the Section 460(e) rules are applied and should be reviewed in conjunction with the gross receipts test under Section 448(c), the Section 263A uniform capitalization rules, and the taxpayer's current method of accounting.

The key planning point is that projects previously dismissed as too large or too long for the old home construction framework may now warrant another look. Contract timing, expected completion period, and accounting method assumptions should be reviewed before the contract is signed.

Who should review the Section 70430 exception now

The expanded rule is most relevant to these taxpayer groups:

1. Single-family homebuilders operating as Individuals, S Corporations, or Partnerships
2. Multifamily developers operating as C Corporations or pass-through entities, since apartments, condominiums, student housing, and senior housing benefit most from the broader language
3. General contractors that need to confirm whether each project qualifies based on actual work performed and property being improved
4. Specialty contractors in electrical, plumbing, HVAC, framing, roofing, and site work that need contract-by-contract review
5. Tax advisors who can use Section 70430 as a discovery prompt for clients with long-term residential jobs and cross-tax-year projects

How much income timing can shift under the expanded exception

The value of the expanded exception depends on contract size, margin, completion timing, and the method used. A few scenarios show why the issue deserves attention.

Scenario one. A residential contractor signs a $12 million multifamily contract expected to generate $1.8 million of gross profit. At year-end 2026, the project is 35 percent complete. Under a percentage-of-completion approach, the contractor may recognize approximately $630,000 of gross profit in 2026. At a 30 percent combined tax rate, that creates about $189,000 in tax before the project is finished. After OBBBA's residential construction contract framing, that $189,000 may shift to the completion year, a meaningful working-capital improvement.

Scenario two. A builder has three qualifying residential contracts that each run across tax years. Method timing can affect whether income and deductions land in the same year, and a clean project-level review may help the builder avoid recognizing income from one job before losses or cost overruns from another job are reflected.

Scenario three. A growing construction firm crossed into larger multifamily work in 2026. Under the OBBBA language, those projects may need to be retested as residential construction contracts. The retest can affect estimated tax payments, covenant planning, and owner distributions.

These examples are timing illustrations, not guaranteed savings. Builders evaluating entity changes during a deferral window should also consider Late S Corporation elections or Late C Corporation elections before the next contract cycle.

What builders should document for the Section 70430 exception

A defensible Section 70430 position depends on five pillars of documentation:

• Signed contract review. Confirm contract date, commencement date, expected completion date, project scope, contract price, change-order terms, and whether the work covers dwelling units and related site improvements.
• Project budget and cost allocation. The 80 percent cost concept remains central to distinguishing residential construction contracts, so cost estimates should tie to job-cost records.
• Work-in-process schedules by contract. Separate costs, billings, retainage, and estimated gross profit by project, and coordinate with Depreciation and amortization elections on equipment used across jobs.
• Current accounting method confirmation. A builder cannot switch methods informally. Some changes require a formal method change request, as outlined in IRS Publication 538 and on Form 3115
• Section 263A and gross receipts evaluation. Analyze the expanded exception alongside capitalization rules and the indexed gross receipts test under Section 448(c)

Common mistakes builders should avoid

Builders should avoid five common mistakes when applying Section 70430.

The first mistake is assuming every construction contract is now exempt. Section 70430 covers residential contracts only, not commercial, industrial, governmental, or infrastructure work.

The second mistake is treating residential construction as a marketing label instead of a statutory definition. The actual contract terms and cost allocations matter more than the project name.

The third mistake is ignoring the effective date. Calendar-year taxpayers generally start with contracts entered into in 2026 and later. Older contracts may remain under prior law.

The fourth mistake is forgetting method-change mechanics. A tax position can be technically available but still require procedural steps before it appears on a return.

The fifth mistake is waiting until filing season. By then, the contract is signed, the job-cost system is running, and estimated tax decisions are already made.

How advisors should use Section 70430 in planning

For CPA firms and tax advisory teams, Section 70430 connects a specific OBBBA provision to cash flow, job costing, and owner planning.

Ask construction clients for a list of residential contracts they have signed or expect to sign in 2026. Flag contracts expected to cross tax years, especially multifamily and larger residential jobs. Ask whether each contract is expected to finish within three years from commencement. Then compare the current accounting method assumption to the updated Section 460 language, and review the applicable State Tax Deadlines for state-level conformity.

Advisors should also coordinate with the client's controller or bookkeeper. If job costs are not tracked cleanly by contract, the tax method analysis becomes harder to support. If retainage, change orders, and overhead allocations are not recorded consistently, the year-end review may turn into a cleanup project.

This is also a good moment to revisit estimated taxes. Deferring income may reduce current-year estimated payments, while completion-year recognition may increase tax later. The better question is not whether to defer income, but what the project cash-flow curve looks like after tax.

How Instead supports construction tax planning under OBBBA

Section 70430 gives builders and advisors a clear reason to review contracts before they are signed, identify which projects qualify for the expanded exception, and model income timing under the taxpayer's permissible methods. Visit Instead's comprehensive tax platform to track contract dates and coordinate construction tax planning across clients and entities. Instead's intelligent system helps construction teams draft tax memos that tie contract facts to Section 460 conclusions, maintain tax workpapers for contract dates and cost allocations, coordinate tax research for residential construction contract analysis, model tax estimates under different method assumptions, and run tax return review s of the method positions taken. Review pricing plans to find the support tier that matches your firm's workflow.

Frequently asked questions

Q: Does OBBBA eliminate percentage-of-completion accounting for every builder?

A: No. Section 70430 expands the exception for residential construction contracts. Builders with commercial, governmental, industrial, infrastructure, or other nonresidential contracts may still need to use percentage-of-completion accounting unless another Section 460(e) exception applies. The residential focus is intentional, and advisors should confirm contract classification before relying on the exception.

Q: When does Section 70430 actually start applying to contracts?

A: Section 70430 applies to contracts entered into in taxable years beginning after July 4, 2025. For calendar-year taxpayers, that generally means contracts entered into in 2026 and later. Fiscal-year taxpayers should confirm the first taxable year that begins after enactment before applying the rule to a specific contract.

Q: What separates a home construction contract from a residential construction contract?

A: A home construction contract generally focuses on dwelling units in buildings with four or fewer dwelling units. A residential construction contract retains the dwelling-unit concept. Still, it removes the four-unit limitation, which can bring multifamily projects, condominium developments, student housing, and senior housing within Section 460(e) review, even when the prior home-construction framework excluded them.

Q: Does the 3-year rule mean every 3-year residential project automatically qualifies?

A: No. The 3-year reference applies when testing certain residential construction contracts that are not home construction contracts. The taxpayer still needs to review the contract definition, expected completion period, gross receipts test under Section 448(c), Section 263A treatment, and current accounting method rules before concluding the project qualifies.

Q: Can a builder switch to the completed contract method automatically?

A: Not necessarily. The completed contract method may be available for qualifying contracts. Still, the builder should confirm its current accounting method and whether a formal method change request on Form 3115 is required before filing. IRS Publication 538 covers accounting period and method change procedures that often apply.

Q: Why does this matter if the income is only deferred to a later year?

A: Timing can still be valuable. Deferring income from a long-term construction contract may improve current-year cash flow, reduce estimated tax pressure, and align tax recognition more closely with project completion and customer collections. The goal is not permanent elimination of tax, but better matching of tax with project economics.