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Key Deadlines & Action Items
Critical dates for R&D credit claims and OBBBA elections
Checklist
July 6, 2026 — OBBBA Small Business Retroactive Deadline
Absolute final deadline for small business retroactive §174A elections and late §280C(c)(2) elections/revocations via amended returns.
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Guide
R&D Credit Statute of Limitations Guide
IRC §6511 gives 3 years from original filing date. 2022 returns filed April 15, 2023 close April 15, 2026 — before the July 6 OBBBA deadline.
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Checklist
Full 2026 R&D Filing Calendar
March 16, April 15, July 6, September 15, October 15, January 10, 2027 — every key date for pass-throughs, C-corps, individuals, and amended returns.
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Guide
45-Day Perfection Period Through January 10, 2027
The IRS transition period for curing deficient R&D credit refund claims. After January 10, 2027, incomplete claims face summary disallowance.
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