Every 2026 Tax Deadline You Need to Know: The Complete Guide
While April is hands down the month most associated with taxes, effective tax planning doesn’t start (or end!) there. A robust financial plan keeps taxes in focus throughout the year, helping you avoid last-minute stress and make the most of available deductions and credits. This guide covers every major 2026 federal tax deadline, month by month, while providing tips, examples, and planning strategies to help you avoid common mistakes, maximize tax efficiency, and keep your financial life on track.
January 2026: start of the tax year
Kicking off filing season, January is a crucial month for preparation.
Deadlines to note
January 15, 2026: Final 2025 estimated tax payment
Self-employed individuals, freelancers, and those with substantial investment income often pay estimated taxes on a quarterly basis, with the Q4 2025 payment due by January 15. Missing this deadline can result in underpayment penalties calculated based on the amount owed and the length of the delay (e.g., a freelance graphic designer who underpays by $2,000 could face penalties and interest that easily exceed $100, even before considering late-payment fees).
Note: The One Big Beautiful Bill (OBBB) increased limits on certain tax credits and deductions, which could reduce your tax burden in 2025. Call us to learn more.
Late January
Tax season (for filing 2025 annual taxes) begins at the end of January. While most people won’t yet have everything they need to file (e.g., their W-2) at this time, there’s no reason to wait until April when you do have all necessary documents in hand.
January 31, 2026: W-2 and 1099 forms to employees and contractors
Employers must provide W-2s to employees and 1099s to independent contractors, forms summarizing income earned and taxes withheld during the previous year. These are essential for accurate individual filings, with late filings costing employers hundreds of dollars per form—and penalties adding up quickly for those with multiple contractors. Financial institutions also issue 1099s for interest, dividends, and other investment income. Receiving these forms represents the first step for taxpayers in seeking to prepare a complete and accurate return.
Tips for January
Organize receipts, invoices, and prior-year tax documents.
Verify the accuracy of employer and financial institution data.
Set up automatic payments for estimated taxes to prevent missed deadlines.
February 2026: early filing preparations
February is quieter than January but still important for business compliance. It’s also worth noting that if you indeed have all necessary forms in hand, there’s no reason you can’t go ahead and submit your annual taxes in February—saving yourself the stress of a last-minute filing two months later.
Deadlines to note
February 28, 2026: Paper filing deadline for 1099 and 1096 forms
Businesses filing paper versions of 1099 and 1096 forms must submit these by this date (whereas electronic files are due by March 31). Incorrect or late submissions can trigger penalties per form, making it crucial to double-check all information.
Tips for February
Consider e-filing 1099 and 1096 forms for quicker processing and receipt confirmation.
Keep and organize digital/physical copies of all forms.
March 2026: business returns and elections
March is a critical month for partnerships, S corporations, and small businesses.
Deadlines to note
March 16, 2026: Partnership and S corporation returns
Partnerships (Form 1065) and S corporations (Form 1120-S) must file returns or request a six-month extension, with Schedule K-1s also provided to partners and shareholders so they can file individual returns prior to the deadline and thus avoid penalties for the entity and its owners.
March 16, 2026: S corporation election (Form 2553)
Businesses seeking S corporation status must file Form 2553 by this date, knowing a failure to do so goes on to impact taxation for the entire year.
March 31, 2026: Electronic 1099 and 1096 filing
Businesses submitting forms electronically must do so by this date, with E-filing ultimately reducing processing errors and ensuring quicker IRS acknowledgment.
Tips for March
Review partnership and S corporation accounting records early on to avoid last-minute corrections.
Schedule extensions if additional time is needed for accurate reporting.
Submit taxes early, as time and paperwork allow.
April 2026: peak tax season
April is typically the busiest month for taxpayers, with annual filings or otherwise extensions due. If you file an extension, know this is for the form—not the payment—meaning you’ll still owe interest and penalties on payments made after the due date.
Deadlines to note
April 1, 2026: First RMD due for those turning 73 in 2025
Required minimum distributions (RMDs) must be taken from tax-deferred retirement savings accounts beginning at age 73, dictating you take your first distribution by April 1st the year after your 73rd birthday.
April 15, 2026: Tax Day
Although tax filings occur throughout the year, there’s a reason April 15th is known as Tax Day given that the following are all due on this date:
Individual income tax returns (Form 1040) for the 2025 tax year (with an additional 5% per month owed, up to 25%, if you miss the deadline)
C corporation tax returns (Form 1120)
Q1 2026 estimated tax payments
IRA and HSA contributions for the 2025 tax year, possibly reducing taxable income
Extension filings (Form 4868), giving you additional time to submit your return (with taxes owed still paid by April 15th to avoid interest)
HSA contributions for the 2025 tax year (note HSAs can serve as an excellent retirement-savings vehicle if you pay for expenses out of pocket)
April 30, 2026: Payroll Filings
Employers must submit Form 941 for Q1 payroll taxes, with late filings resulting in penalties and interest.
Tips for April
File early to allow time for corrections.
Check that withholding is accurate to prevent underpayment.
Maximize retirement contributions before the deadline.
May 2026: nonprofit organization filings
May is a slower tax month overall—appreciated after the hubbub of April—but that doesn’t mean it’s not without its own deadlines to keep in mind.
Deadlines to note
May 15, 2026: Nonprofit tax returns (Form 990)
Tax-exempt organizations must file Form 990, 990-EZ, or 990-PF to maintain their tax-exempt status. Missing this deadline can trigger penalties or loss of nonprofit status, and nonprofits should gather all financial documentation early on to avoid errors.
June 2026: mid-year review
June is a good time to ensure the efficacy of your current tax strategies, knowing it’s better to make any tweaks now rather than wait until the end of the year (when it may be too late).
Deadlines to note
June 15, 2026: Q2 estimated tax payments
This installment applies to individuals, businesses, and self-employed workers, with late payments known to trigger underpayment penalties.
June 15, 2026: Filing extension for U.S. expats
Americans living overseas enjoy an extra two months to file returns, though any taxes owed are still due by 4/15 (with interest accruing on unpaid balances).
Tips for June
Evaluate estimated payments based on year-to-date income.
Review foreign income tax credits if living abroad.
Adjust withholding as necessary to avoid penalties.
July 2026: retirement plan filings
Several noteworthy filing deadlines occur in July for employers.
Deadlines to note
July 31, 2026: Form 5500 for employer retirement plans
Employers with 401(k)s, pensions, or other retirement plans must file Form 5500 in the absence of an extension request, accurate reporting ensuring compliance with ERISA and IRS regulations.
July 31, 2026: Payroll filings
Q2 Form 941 filings are due for employers
September 2026: Q3 deadlines
The third estimated tax payment of 2026 is due in September for those making quarterly payments.
Deadlines to note
September 15, 2026: Q3 estimated tax payments
Individuals and businesses making quarterly estimated payments must submit the third installment by this date.
September 15, 2026: Extended partnership and S corporation filings
This is the final deadline for any six-month extensions filed in March.
October 2026: extended individual and trust returns
Payments come due in October for extensions filed back in April.
Deadlines to note
October 15, 2026: Extensions due for:
Individual returns filed under an extension
Trust and estate returns on extensions
C corporation returns on extensions
October 31, 2026: Payroll filings
Q3 Form 941 filings are due for employers.
November 2026: planning ahead
November is generally quieter but still involves strategic planning. Consider charitable giving, retirement contributions, and tax-loss harvesting to reduce your overall 2026 tax liability while likewise preparing for December deadlines to prevent last-minute errors and stress.
December 2026: year-end wrap-up
As the year comes to a close, so too does your chance to execute any final tax-advantaged strategies (e.g., charitable donations or retirement savings account contributions).
Deadlines
December 15, 2026: Q4 C corporation estimated taxes
C corporations must submit their final installment of estimated taxes by this date.
December 31, 2026: Final year-end actions
Make tax-deductible charitable contributions for 2026.
Take required minimum distributions (RMDs) from retirement accounts if over age 73.
Conduct year-end tax-loss harvesting.
Contribute to employer-sponsored plans (e.g., FSAs and 401(k)s).
Year-round tax management tips
Automate reminders using a calendar or software.
Partner with tax professionals for complex situations.
Review withholding and estimated payments on a regular basis.
Maximize retirement contributions.
Leverage deductions, credits, and tax-loss harvesting strategies.
Keep payroll taxes up to date.
Track state-level deadlines.
Maintain organized records with respect to income, deductions, and supporting documents for at least three years.
The takeaway on tax deadlines
Staying organized and planning ahead for 2026 tax deadlines won’t just help limit stress but also keep more money in your pocket by taking advantage of tax-saving opportunities. As the 2026 tax season approaches, understanding key deadlines and taking proactive steps to prepare—including seeking professional guidance—can make a significant difference for your financial outlook while saving you time, money, and unnecessary headaches in the process.
Need help with your personal or business taxes? Call us at 201-488-2828 or send an email to support@kaleedscpa.com so we can connect.
