Tax Insights

Tax research, published.

These are working notes from the Signal research desk: the credits, elections, and method changes most generalist preparers do not have time to chase down, cited to statute with IRS source links. Managed firms resell this research to their business clients as advisory work; here it is in the open.

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Practice

Second-Opinion CPA: How a Free Return Review Works

What a second-opinion review of a business return looks for, the items generalist preparers most often leave on the table, and how the free review works.

What did your last return leave behind?

Entity Tax

Should I Be an S-Corp? Late Elections and Reasonable Comp

The break-even math on S-corp elections, late-election relief under Rev. Proc. 2013-30, and the reasonable-compensation standard that keeps the savings defensible.

The break-even is lower than most owners think.

Recovery

Section 174A: The Retroactive R&D Amend Window

OBBBA 2025 restored R&D expensing and opened a retroactive amend window that closes July 6, 2026. Who qualifies and what the recovery looks like.

The amend window closes 7/6/2026.

ERC Q3 2021: The Backlog and Your 941-X

If your 941-X was filed but is still pending, here is where the backlog stands, what the moratorium changed, and how to check status without poking the bear.

Filed but still waiting? You are not alone.

Pass-Through Tax

State PTET Election: The SALT Cap Workaround

Pass-through entity tax elections let owners deduct state taxes at the entity level. Most states have one; most eligible owners have never made the election.

The SALT cap workaround most owners are missing.

Exit & Equity

QSBS Section 1202: The Gain Exclusion

Qualified small business stock can exclude millions in gain at exit. The eligibility tests, the five-year clock, and the planning moves that preserve it.

Exit gain exclusion, if the clock was started.

Compliance

BOIR Filing Requirements: FinCEN Beneficial Ownership

Who has to file a FinCEN beneficial ownership report, who is exempt, current deadlines, penalty exposure, and what to do if the original window was missed.

Who actually has to file, in plain English.

Credits

The R&D Credit (IRC Section 41)

The most under-claimed credit in small-business tax: the four-part test, qualified research expenses, the payroll-tax offset for startups, and substantiation.

The most under-claimed small-business credit.

Depreciation

Cost Segregation: Hidden Depreciation in Buildings

Reclassifying building components into 5, 7, and 15 year property frontloads deductions; Form 3115 catch-up recovers prior years without amending.

Typical one-time recovery: $25K to $200K.

Deductions

Section 179D: The Energy-Efficient Building Deduction

Up to $5.00 per square foot for qualifying lighting, HVAC, and envelope work, including the designer-allocation path most regional A/E firms have never claimed.

Up to $5.00 per square foot, often unclaimed.

The Augusta Rule: Section 280A(g)

Renting your home to your business up to 14 days a year, tax-free: the fair-market-rent standard, the Sinopoli caveats, and the documentation that survives exam.

14 days a year, tax-free, if documented right.

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The research desk is one capability inside the Signal fee: productized research your firm resells to its business clients as advisory engagements. If you run a firm, the more interesting question is what the rest of the catalog does to your week.

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