2026 federal and California calendar
Tax deadlines and planning dates for 2026.
Common calendar-year filing and payment dates for individuals, estates, trusts, partnerships, S corporations, and C corporations, with the questions that can change each deadline.
01
Individual and fiduciary dates
These are common dates for 2025 calendar-year returns filed in 2026, before taxpayer-specific relief or special filing rules. An extension to file generally does not extend the regular payment deadline.
| Return and jurisdiction | Regular filing/payment date | Extended filing date |
|---|---|---|
| Federal individual / Form 1040 or 1040-SR | April 15, 2026 | October 15, 2026, with a timely extension request |
| Federal ordinary estate or trust / Form 1041 | April 15, 2026 | September 30, 2026, with a timely Form 7004; special fiduciary returns can differ |
| California individual / Form 540 or 540NR | April 15, 2026 | October 15, 2026, under California’s automatic filing extension |
| California fiduciary / Form 541 | April 15, 2026 | October 15, 2026, under California’s automatic filing extension |
The federal and California fiduciary extension dates differ. Confirm the estate or trust’s tax year and form before using either date. Sources: IRS individual filing rules, 2025 Form 1041 instructions, and FTB e-file calendar.
2026 individual estimated payments
For individuals who must make estimated payments, the regular calendar-year schedule below applies before special rules or relief. These are payments toward 2026 tax, separate from a balance due on a 2025 return.
| Payment date | Federal installment | California standard installment |
|---|---|---|
| April 15, 2026 | First | 30% |
| June 15, 2026 | Second | 40% |
| September 15, 2026 | Third | 0% |
| January 15, 2027 | Fourth | 30% |
California’s standard installment percentages differ from federal. Required amounts depend on withholding, credits, prior-year tax, income, and any applicable annualized-income or other special rules. See IRS Publication 505 (2026) and FTB estimated-tax guidance.
02
Business return dates
The dates below concern 2025 calendar-year income-tax returns filed in 2026. They assume the ordinary filing schedule and a valid extension where required; fiscal years, special entities, and disaster relief can change the result.
| Return and jurisdiction | Regular filing date | Extended filing date |
|---|---|---|
| Federal partnership / Form 1065 | March 16, 2026 | September 15, 2026 |
| Federal S corporation / Form 1120-S | March 16, 2026 | September 15, 2026 |
| Federal C corporation / Form 1120 | April 15, 2026 | October 15, 2026 |
| California S corporation / Form 100S | March 16, 2026 | September 15, 2026 |
| California C corporation / Form 100 or 100W | April 15, 2026 | November 16, 2026 |
| California partnership / Form 565 | March 16, 2026 | October 15, 2026 |
March 15 falls on a Sunday in 2026, which moves the ordinary March filing date to March 16. California’s C corporation and partnership filing extensions differ from their federal counterparts. Sources: IRS Publication 509 (2026), FTB Form 3539 instructions for 2025 returns, and FTB business e-file calendar.
Before requesting an extension, identify the return, estimate any tax due, and coordinate K-1 delivery with the owner’s filing. The business tax preparation checklist outlines the records to gather.
03
The planning dates behind the deadlines
A useful calendar includes decision dates before the filing deadline.
Sources and limits
Verify the rules for your form and tax year.
Calendar sources were checked October 28, 2026. This overview does not determine a particular taxpayer’s deadline, extension eligibility, payment amount, or disaster-relief entitlement. It does not cover every return, fiscal year, employer deposit, information return, excise tax, sales tax, property tax, foreign report, or local requirement.
- IRS Publication 509: Tax Calendars (2026)
- IRS Publication 505: 2026 estimated-tax payments
- IRS Form 1041 instructions: 2025 calendar-year estates and trusts
- California FTB e-file calendars: individual, fiduciary, and business returns
- California FTB Form 3539: corporate extension dates for 2025 returns
- California FTB individual estimated-tax installments
- IRS disaster-relief notices and covered localities
Read the current notice for your location and the instructions for the specific form. A federal postponement does not by itself establish identical California or local treatment. If a deadline may have passed, contact the team with a high-level summary of the agency, return type, tax year, and stated deadline. Wait for secure document instructions before sharing notices or sensitive records.
Related next steps
Services related to this guide.
The service scope depends on your records, entities, states, transactions, deadlines, and goals.
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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