May 1, 2026 (Disaster Relief Deadline): Affected taxpayers in specific areas have this date for 2025 IRA/HSA contributions, Q1 2026 estimated taxes, and first-quarter payroll/excise taxes.

May 15, 2026 (Monthly Employer Deposits): Employers must deposit Social Security, Medicare, and withheld income tax for April 2026.

May 15, 2026 (Non-profit): Calendar year non-profits (Form 990) must file or request an extension.

May 31, 2026 (Payroll Taxes): First-quarter 2026 payroll tax returns (Form 941) are due, if not filed in April, for those who deposited in full.

Monthly Deposits: Semi-weekly depositors must deposit payroll taxes for specific dates throughout the month.

Important Reminders:

Extensions: While individual income tax filing extensions are due on October 15, 2026, any tax owed was due on April 15, 2026.

Disaster Relief: Some taxpayers may have deadlines postponed by the IRS.

Stay Compliant: Employers should ensure timely monthly deposits to avoid penalties.