Tax Season 2026: Key Dates and Events

The 2026 tax filing season officially began on January 26, when the Internal Revenue Service (IRS) opened the filing window. To help our clients stay ahead, we’ve compiled a month-by-month guide below with the key tax dates and events for 2026.

January 2026

• 1/15/26 – Q4 2025 estimated tax payments due for both individual filers (self-employed individuals and independent contractors) and businesses. See (Form 1040-ES).
• 1/26/26 – 2025 Tax Season officially begins for both individual filers and businesses.

February 2026

• 2/2/26 – Due date for employers to process and send out W-2 and 1099 forms (specifically 1099-NEC, 1099-MISC, and 1099-K) to any independent contractor utilized in 2025. Deadline applies whether filing via paper or electronically.
• 2/15/26 – Due date for individual filers to file Form W-4 to reclaim exemptions from withholding.
• 2/28/26 (3/2) – Information Returns, Paper filings of (forms 1095-C, 1097, 1098, 1099, 3921, 3922, 8027), and W-2G are due. (E-filing deadline is later.)

March 2026

• 3/16/26 – S Corporation (IL-1120-S) Illinois state return due.
• 3/16/26 – Federal Partnership (Form 1965) and S-Corporation (Form 1120S) Tax returns due; deadline to file business extension (Form 7004). (Federal).
• 3/31/26 – E-file deadline for various informational returns (e.g., 1094/1095 series).

April 2026

• 4/1/26 – Electronic filings of forms (1095-C, 1097, 1098, 1099, 3921, 3922, 8027), and W-2G are due.
• 4/1/26 – Required minimum distribution (RMD) due for individual filers who turned 72 years old in 2025 from retirement account.
• 4/15/26 – Tax Day 2025. (Form 1040).
• 4/15/26 – FinCEN (Form 114/FBAR).
• 4/15/26 – Deadline for individual filers to file for an extension (Form 4868).
• 4/15/26 – Deadline for individual filers to make IRA and HSA contributions for 2025 tax year.
• 4/15/26 – Q1 2026 estimated tax payments due for both individual filers (self-employed individuals and independent contractors) and businesses.
• 4/15/26 – Taxes due for calendar year businesses categorized as C-Corporations. (Form 1120).
• 4/15/26 – Deadline to file a trust (Form 1041) or gift tax return (Form 709).

May 2026

• 5/15/26 – Deadline to file a calendar year nonprofit or private foundation return.
• 5/31/26 – Deadline for (Forms 5498, 5498-ESA, 5498-QA and 5498-SA).

June 2026

• 6/15/26 – Q2 2026 estimated tax payments due for both individual filers (self-employed individuals and independent contractors) and businesses.

July 2026

• 7/31/26 – Deadline to file an employment benefit information return (Form 5500) or extension.

September 2026

• 9/15/26 – Q3 2026 estimated tax payments due for both individual filers (self-employed individuals and independent contractors) and businesses.
• 9/15/26 – Extended deadline to file returns for calendar year businesses categorized as Extended Partnerships and S-corporations. See (Form 7004).
• 9/30/26 – Extended deadline to file returns for trusts and estates of calendar year entities. See (Form 7004).

October 2026

• 10/15/26 – Extended deadline to file 2025 tax returns for individual filers. See (Form 4868).
• 10/15/26 – Extended deadline to file tax returns for calendar year businesses categorized as C-Corporations. See (Form 7004).
• 10/15/26 – Extended deadline to file tax returns for employee benefit plans. See (Form 5558).
• 10/15/26 – Extended deadline to file FinCEN. See (Form 114/FBAR).

November 2026

• 11/15/26 – Deadline for extended nonprofit or exempt organization’s return. See (Form 8868).

December 2026

• 12/31/26 – Required minimum distributions (RMDs) must be taken for individual filers aged 73 years or older by the end of 2025.

January 2027

• 1/15/27 – Q4 2026 estimated tax payments due for both individual filers (self-employed individuals and independent contractors) and businesses.

Should you have any questions about this year’s tax calendar, we encourage you to reach out to your Weiss tax advisor.