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Sources & methodology
We cite a primary or authoritative source for every number, date-stamp the content, and flag what’s still unsettled.
Primary & authoritative sources
- IRS — OBBBA deductions fact sheet
- IRS — car-loan interest guidance (IR-2025-129)
- IRS — 2025 lender transition relief (Notice 2025-57)
- IRS — draft Form 1098-VLI instructions
- Federal Register — proposed regulation (Jan 2, 2026)
- NHTSA VIN Decoder (U.S. assembly check)
- Thomson Reuters — deduction overview
- RSM US — understanding the deduction
- Iowa State CALT — proposed-reg analysis
- Current Federal Tax Developments — technical analysis
- CNBC — real-world savings magnitude
How we keep it honest
- Date-stamped: content is current as of June 2026 and reviewed as guidance changes.
- Proposed, not final: the IRS implementing rules are proposed regulations (Federal Register, Jan 2, 2026) plus Notice 2025-57 transition relief — details can change. Fed. Register
- We flag the unsettled bits: head-of-household / married-filing-separately phase-out thresholds, ATV eligibility, and multi-owner splits are not yet specified — we say so rather than guess.
- Not advice: this is educational information, not tax, legal, or financial advice. Verify with the IRS or a professional before filing.
- Independent: not affiliated with the IRS or any government agency.