Here’s what HIVE AI had to say about “How does the IRS define the 2025 tax year for 2026 filings?”:
How the IRS defines “tax year 2025” for 2026 filings
For the 2026 filing season, “tax year 2025” means the taxpayer’s taxable year that ended during 2025 (for most individuals, the calendar year ending December 31, 2025).
- If you are a calendar-year taxpayer (the most common for individuals), an entire tax year runs from January 1 through December 31, so tax year 2025 is January 1, 2025 through December 31, 2025. 2
- More generally, the IRS describes a tax year as an annual accounting period used to keep records and report income and expenses; the tax year can be a calendar year or a fiscal year. 1
So, for “2026 filings” (returns filed in 2026 during the 2026 filing season), “tax year 2025” generally refers to the 12-month period that is either:
- Calendar year 2025 (January 1, 2025 through December 31, 2025), or
- A fiscal year that began in 2025 and ended in 2026 (for taxpayers using a fiscal year). 3
Sources
1 – IRS.gov – Tax years
2 – Foreign earned income exclusion – bona fide residence test
3 – Instructions for Form 1120 (2025)
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