2026 federal and California calendar
Tax deadlines and planning dates to keep visible in 2026.
A practical overview of common calendar-year filing and payment dates for individuals, estates, trusts, partnerships, S corporations, and C corporations—plus the questions that can change the deadline.
01
Individual and fiduciary dates
Confirm whether the filing is an individual return, a fiduciary return, or another return before relying on a date.
| Common 2026 date | What it may cover | Important distinction |
|---|---|---|
| April 15 | Most 2025 calendar-year individual returns; California individual and fiduciary returns; first 2026 individual estimated payment | An extension to file generally does not extend time to pay. |
| June 15 | Second 2026 individual estimated payment; certain taxpayers abroad; California PTE elective-tax payment considerations | Different rules and qualifications apply to each item. |
| September 15 | Third 2026 individual estimated payment; extended calendar-year partnership and S corporation returns | Entity and fiscal-year status matter. |
| October 15 | Many extended 2025 individual returns; California automatic extension date for timely filing | Payment may have been due earlier. |
| January 15, 2027 | Fourth 2026 individual estimated payment | Withholding and safe-harbor facts affect the amount. |
02
Business return dates
Business deadlines follow the entity’s tax classification and year end, not merely the business name.
| Calendar-year return | Regular federal pattern | What to confirm |
|---|---|---|
| Partnership / Form 1065 | 15th day of the third month after year end | K-1 readiness, extension, states, and owner returns |
| S corporation / Form 1120-S | 15th day of the third month after year end | Compensation, payroll reports, basis, K-1s, and states |
| C corporation / Form 1120 | Generally 15th day of the fourth month after year end | Year end, special June-year rules, estimates, and states |
| Estate or trust / Form 1041 | Generally 15th day of the fourth month after year end | Entity type, tax year, distributions, K-1s, and final year |
03
The planning dates behind the deadlines
A useful calendar includes decision dates before the filing deadline.
Sources and limits
Verify current rules before acting.
This guide summarizes common dates and does not cover every form, jurisdiction, fiscal year, disaster postponement, employer deposit, information return, excise tax, sales tax, property tax, foreign reporting, or local requirement. Confirm the current official calendar for the specific taxpayer and filing.
Related next steps
Connect the checklist to the right work.
General guidance can help you prepare. Your records, entities, states, transactions, deadlines, and goals determine the actual scope.
Does an extension give me more time to pay?
Generally, an extension provides more time to file, not more time to pay. Estimate and payment requirements should be reviewed by the regular due date.
Why can my deadline differ from the dates shown?
Entity type, tax year, jurisdiction, residency, form, weekends, holidays, disaster relief, and other facts can change the applicable date.
Are estimated payments always equal?
Not necessarily. Withholding, prior-year tax, current income, annualization, state rules, entity payments, and safe-harbor provisions can affect the amount and timing.
Does this calendar cover payroll and sales tax?
No. Employer deposits, payroll returns, sales tax, information returns, excise taxes, property taxes, and local filings follow separate rules and calendars.
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