This comprehensive calendar outlines key tax payment and filing deadlines for 2026, including individual estimated tax payments, payroll tax deposit schedules, corporate estimated tax payments, return filing dates with extension details, federal payroll tax return deadlines, Texas unemployment insurance reporting, and guidance on underpayments, late payments, and late filings.

Table of Contents

  1. Individual Estimated Tax Payments
  2. Payroll Tax Payments
  3. C Corporation Estimated Tax Payments
  4. Retirement Plan Contributions
  5. Return Filing Due Dates
  6. Federal Payroll Tax Returns
  7. Texas Unemployment Insurance Reports
  8. Individual Underpayments, Late Payments, and Late Filings
  9. Business Underpayments, Late Payments, and Late Filings

1) Individual Estimated Tax Payments

Installment Payment Period Covered Due Date
1st Jan 1 to Mar 31, 2026 April 15, 2026
2nd Apr 1 to May 31, 2026 June 15, 2026
3rd Jun 1 to Aug 31, 2026 September 15, 2026
4th Sep 1 to Dec 31, 2026 January 15, 2027

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2) Payroll Tax Payments

  • Monthly Depositor: Deposit by the 15th of the following month.
  • Semi-Weekly Depositor: Paydays on Wednesday, Thursday, or Friday → Deposit by the following Wednesday; Paydays on Saturday, Sunday, Monday, or Tuesday → Deposit by the following Friday.
  • Next-Day Deposit Rule: If $100,000 or more in taxes is accumulated on any day, deposit by the next business day.

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3) C Corporation Estimated Tax Payments

Installment Payment Period Covered Due Date
1st Jan 1 to Mar 31, 2026 April 15, 2026
2nd Apr 1 to May 31, 2026 June 15, 2026
3rd Jun 1 to Aug 31, 2026 September 15, 2026
4th Sep 1 to Dec 31, 2026 December 15, 2026

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4) Retirement Plan Contributions

For 2026, individuals can contribute to IRAs until April 15, while elective deferrals for 401(k), 403(b), and SIMPLE IRA plans must be made by December 31. Employer contributions, including SEP IRAs and Solo 401(k), can be made after year end, up to the employer’s tax filing deadline (including extensions).

5) Return Filing Due Dates

Return Type Original Due Date Extension Due Date Extension Form & Link Links
Form 1120S (S Corporation) March 16, 2026 September 15, 2026 https://www.irs.gov/forms-pubs/about-form-7004 https://www.irs.gov/forms-pubs/about-form-1120-s
Form 1065 (Partnership) March 16, 2026 September 15, 2026 https://www.irs.gov/forms-pubs/about-form-7004 https://www.irs.gov/forms-pubs/about-form-1065
Form 1040 (Individual) April 15, 2026 October 15, 2026 https://www.irs.gov/forms-pubs/about-form-4868 https://www.irs.gov/forms-pubs/about-form-1040
Form 1120 (C Corporation) April 15, 2026 October 15, 2026 https://www.irs.gov/forms-pubs/about-form-7004 https://www.irs.gov/forms-pubs/about-form-1120
Form 1041 (Estates & Trusts) April 15, 2026 September 30, 2026 https://www.irs.gov/forms-pubs/about-form-7004 https://www.irs.gov/forms-pubs/about-form-1041
Form 709 (Gift Tax Return) April 15, 2026 October 15, 2026 https://www.irs.gov/forms-pubs/about-form-8892 https://www.irs.gov/forms-pubs/about-form-709
Form 990 (Tax-Exempt Organizations) May 15, 2026 November 16, 2026 https://www.irs.gov/forms-pubs/about-form-8868 https://www.irs.gov/forms-pubs/about-form-990
Form 5500 (Employee Benefit Plan) July 31, 2026 October 15, 2026 https://www.irs.gov/forms-pubs/about-form-5558 https://www.dol.gov/agencies/ebsa/employers-and-advisers/plan-administration-and-compliance/reporting-and-filing/form-5500
Form 706 (Estate Tax Return) 9 months after date of death 6-month extension https://www.irs.gov/forms-pubs/about-form-4768 https://www.irs.gov/forms-pubs/about-form-706

6) Federal Payroll Tax Returns

Form / Obligation Period Due Date IRS Link
Form 941 (Quarterly) Q4 2025 Feb 2, 2026 https://www.irs.gov/forms-pubs/about-form-941
Form 941 (Quarterly) Q1 2026 Apr 30, 2026 https://www.irs.gov/forms-pubs/about-form-941
Form 941 (Quarterly) Q2 2026 Jul 31, 2026 https://www.irs.gov/forms-pubs/about-form-941
Form 941 (Quarterly) Q3 2026 Nov 2, 2026 https://www.irs.gov/forms-pubs/about-form-941
Form 940 (FUTA) Annual Feb 2, 2026 https://www.irs.gov/forms-pubs/about-form-940
Form W-2 / W-3 Annual Feb 2, 2026 https://www.irs.gov/forms-pubs/about-form-w-2
Form 1099-NEC Annual Feb 2, 2026 https://www.irs.gov/forms-pubs/about-form-1099-nec
Form 943 / 944 / 945 Annual Feb 2, 2026 https://www.irs.gov/forms-pubs/about-form-943

7) Texas Unemployment Insurance Reports

Quarter Due Date
Q1 Apr 30, 2026
Q2 Jul 31, 2026
Q3 Oct 31, 2026
Q4 Jan 31, 2027

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8) Individual Underpayments, Late Payments, and Late Filings

Underpayment Penalty

Applies if you do not pay enough estimated tax during the year. Calculated based on the amount underpaid, the period of underpayment, and quarterly IRS interest rates.

Late Payment Penalty

Rate: Generally 0.5% per month (or part of a month) on unpaid tax, up to 25%.

When It Begins: Starts the day after the original due date of the return and continues until the tax is paid in full or reaches the maximum cap.

Late Filing Penalty

Rate: Usually 5% per month (or part of a month) on unpaid tax, up to 25%.

When It Begins: Starts the day after the original due date of the return and accrues for each month or part of a month the return is late.

Effect of Extensions: Filing an extension (e.g., Form 4868) extends the time to file, not the time to pay. If you file by the extended due date, the late filing penalty does not apply. However, any unpaid tax after the original due date will still accrue late payment penalties and interest.

Important Note: If both late filing and late payment penalties apply for the same month, the late filing penalty is reduced by the late payment penalty for that month.

9) Business Underpayments, Late Payments, and Late Filings

Underpayment Penalty for Corporations

Applies if estimated tax payments are insufficient or late. Calculated using Form 2220 and quarterly interest rates.

Late Payment Penalty

Rate: 0.5% per month (or part of a month) on unpaid tax, up to 25%.

When It Begins: Starts the day after the original due date of the return and continues until the tax is paid in full or reaches the maximum cap.

Late Filing Penalty

Rate: 5% per month (or part of a month) on unpaid tax, up to 25%.

When It Begins: Starts the day after the original due date of the return and accrues for each month or part of a month the return is late.

Effect of Extensions: Filing an extension (e.g., Form 7004) extends the time to file, not the time to pay. If you file by the extended due date, the late filing penalty does not apply. However, any unpaid tax after the original due date will still accrue late payment penalties and interest.

Important Note: If both late filing and late payment penalties apply for the same month, the late filing penalty is reduced by the late payment penalty for that month.