State Conformity Gaps After OBBBA: Why Your Section 174A Strategy Can’t Stop at the Federal Return

The One Big Beautiful Bill Act restored immediate expensing for domestic research expenses under new Section 174A, and most tax teams treated that as good news and moved on to the next issue. For a multistate Fortune 100 filer, the federal change only covers half the story. States don’t automatically follow federal law, and several states that decoupled from prior Section 174 amortization rules haven’t adopted 174A on the same timeline, and some haven’t adopted it at all.

We touched on this shift in our overview of what tax teams need to know about R&D credits this year. This post looks closer at the state-by-state exposure that a federal-only view tends to miss.

Why Conformity Isn’t Automatic

Some states adopt the Internal Revenue Code as currently in effect, which means federal changes flow through without any additional legislative action. Other states use a fixed conformity date, adopting the code as it existed on a specific day, which means a federal change like Section 174A doesn’t apply at the state level until the legislature votes to update that date. A handful of states decouple from federal research expensing rules entirely and set their own standards, independent of whatever Congress does at the federal level.

For an organization filing in dozens of states, this creates a genuine patchwork. Your federal return might reflect full domestic research expensing under 174A, while three or four states where you file still require amortization under their own separate rules, or apply a different treatment to the same expenditure altogether.

Where This Creates Real Exposure

Under-claiming a state benefit happens often, and it costs money, but it isn’t the only risk here. Inconsistency between your federal and state filings creates a second, arguably larger problem, because it draws attention during routine review. If your state return doesn’t reflect the correct addback or adjustment for a state that hasn’t conformed to 174A, you’ve created a discrepancy that a state auditor can spot right away by comparing your federal and state taxable income reconciliation.

This matters more for organizations with material R&D spend concentrated in a handful of states. If your largest research operations sit in a state with a fixed conformity date that predates OBBBA, the amortization requirement there could differ substantially from your federal treatment, and that difference has to show up correctly on every return you file in that state, not just the ones your team happens to review most closely.

Building a State-by-State Conformity Map

Start with a straightforward exercise: list every state where you file, and classify each one by its conformity approach. Rolling conformity states generally require the least manual tracking, since federal changes flow through on their own. Fixed-date conformity states need a check against whether the legislature has updated that date since OBBBA passed. Decoupled states need their own dedicated research, because they set the rules independently and won’t necessarily follow federal treatment even after enough time has passed.

This map isn’t something you build once and file away. State legislatures update conformity dates during regular sessions, often with little advance notice, so a map built in early 2026 may already be out of date by the time you file. Build a review cadence into your process instead of treating this as a single point-in-time analysis you never revisit.

State Credits Add Another Layer

Beyond conformity to the federal expensing rules, many states offer their own R&D tax credits with separate eligibility requirements, separate documentation standards, and separate filing deadlines. A multistate organization that only optimizes its federal Section 41 credit is likely leaving state-level incentives on the table without realizing it. Our state tax incentives work exists to help large filers identify where those opportunities sit and how to capture them without duplicating effort already done at the federal level.

Coordinating Federal and State Strategy

Organizations that handle this well treat federal Section 174A elections and state conformity analysis as one coordinated project, rather than two separate workstreams handled by different teams on different timelines. Our 174 assistance work bridges that gap directly, helping tax teams confirm their federal capitalization and expensing decisions translate correctly into every state where they file, instead of assuming a level of conformity that may not actually exist.

What to Do Before Your Next Filing Cycle

Pull your current state filing footprint and run it against a conformity checklist before you finalize any amended returns or retroactive elections. Confirm which states require an addback, which states already conform on their own, and which states need a separate state-specific election you haven’t made yet.

Federal law changed quickly this year. State law is catching up at very different speeds from state to state, and some states may not move at all in the near term. A tax team that only reviews its federal position risks getting the largest number right while getting several smaller ones wrong, and those smaller errors add up quickly across a large multistate footprint.

Where to Start

Pick the five states where your organization has the largest research footprint, and confirm each one’s current conformity status before this quarter closes. That short list will tell you more about your real exposure than a broad review of all fifty states, and it gives you a clear starting point instead of an open-ended research project with no deadline attached. If you’d rather talk through your specific state footprint than build the checklist from scratch, reach out and we can walk through it together.

Jason Massie, CPA, Esq.

As the Founder and President of MASSIE R&D Tax Credits, Jason is responsible for the quality, consistency, and integrity of our services. His strategic vision and leadership drive innovation within the company, encouraging collaboration and ne...