As a former IRS auditor who’s navigated decades of tax code changes, I have to say 2026 is bringing an unprecedented level of complexity. Between the One Big Beautiful Bill’s sweeping changes, 43 states implementing their own tax modifications, and ongoing tariff uncertainty affecting business expense classifications, we’re all facing a regulatory landscape that shifts depending on jurisdiction, sunset dates, and even pending court decisions.
The Federal Picture: Temporary Relief with Expiration Anxiety
Let’s start with what changed federally. The One Big Beautiful Bill (signed July 4, 2025) made several significant adjustments:
SALT Deduction Relief: The state and local tax deduction cap jumped from $10,000 to $40,400 for tax year 2026. But here’s the catch - it increases by only 1% annually after 2026, then reverts completely back to $10,000 on January 1, 2030. If you’re in a high-tax state like California or New York, you need to track this right now to maximize the benefit during this temporary window.
New Car Loan Interest Deduction: Up to $10,000 of car loan interest is now deductible for tax years 2025-2028. This is entirely new territory - we haven’t had this since the TCJA eliminated it in 2017. But it’s temporary, and clients are already confused about how it interacts with vehicle depreciation and Section 179 expensing.
Bonus Depreciation Made Permanent: The 100% depreciation allowance is no longer phasing out. Equipment purchases just got more attractive, but the planning calculations completely changed overnight.
Standard Deduction Increases: $32,200 for married filing jointly, $16,100 for single filers, $24,150 for heads of households. The ~2.7% inflation adjustment means marginal cases need recalculation.
State Chaos: 43 Different Directions
Here’s where it gets really messy. 43 states implemented notable tax changes for 2026, and they’re not moving in concert:
- Michigan increased gas taxes from 31¢/gallon to 51¢/gallon with future inflation adjustments
- Oklahoma collapsed from 6 income tax brackets down to 3 and reduced the top rate from 4.75% to 4.5%
- Some states are raising taxes while others are cutting them
- Multi-state businesses now need jurisdiction-specific expense tracking
If you have clients operating in multiple states, how are you tracking which expenses qualify where? The deductibility rules are diverging significantly.
The Tariff Wild Card
Tariffs are at their highest levels in nearly a century, and a Supreme Court decision pending this session could invalidate a significant portion of current tariffs. For businesses:
- Supply chain costs are volatile and potentially non-deductible depending on the ruling
- Section 162 “ordinary and necessary” business expense standards apply, but what’s “ordinary” when policy changes monthly?
- Documentation requirements are crucial - you need clear audit trails showing business purpose
The Beancount Metadata Strategy
This is exactly where plain text accounting shines. Here’s what I’m recommending to clients:
Use tags for jurisdictions:
Track sunset dates with metadata:
Document regulatory uncertainty:
Build queries for monitoring:
- Running totals against thresholds (SALT $40,400 cap)
- Sunset date alerts (car loan interest expires 2028)
- Multi-state expense summaries
- Tariff cost tracking for potential adjustments
My Questions for the Community
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How are you tracking expenses that have different deductibility rules by state? Separate accounts per jurisdiction? Metadata tags? Custom queries?
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Anyone built Beancount queries that alert when approaching temporary provision caps? (e.g., SALT deduction threshold, car loan interest limit)
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For multi-state businesses: What account structure are you using? Do you have state-specific expense sub-accounts, or are you relying entirely on metadata?
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Tariff costs: How are you documenting business necessity given the regulatory uncertainty and potential Supreme Court changes?
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Sunset date tracking: What’s your workflow for ensuring temporary deductions don’t slip through when they expire in 2028 or 2030?
The regulatory environment feels more chaotic than it’s been in decades. The plain text, version-controlled nature of Beancount means we can document our interpretation of the rules, track changes over time, and adapt as regulations shift.
I’d love to hear how others are handling this complexity. What metadata strategies are working? What queries have you built? Where are you struggling?
Sources: IRS 2026 inflation adjustments, Tax Foundation state tax changes, One Big Beautiful Bill provisions, Grant Thornton 2026 business tax planning guide