Your All-in-One Tax Resource Center
Stay organized and informed with our easy-to-use tax resource hub. From important deadlines to refund tracking tools, O’Hara & Company keeps Suffolk County taxpayers connected to the essentials—without the clutter.
Know Your Key Tax Due Dates
Never miss a filing deadline again. Whether you’re an individual, small business, or nonprofit, keeping track of IRS and NYS due dates is essential. Our calendar highlights the most common federal and state filing dates so you can plan ahead with confidence.
September 2025
Individuals
September 10
Report August tip income of $20 or more to employers (Form 4070).
September 15
Pay the third installment of 2025 estimated taxes (Form 1040-ES), if not paying income tax through withholding or not paying sufficient income tax through withholding.
Employers
September 15
Deposit nonpayroll withheld income tax for August if the monthly deposit rule applies.
September 15
Deposit Social Security, Medicare and withheld income taxes for August if the monthly deposit rule applies.
Calendar-year partnerships
September 15
File a 2024 income tax return (Form 1065 or Form 1065-B) and provide each partner with a copy of Schedule K1 (Form 1065) or a substitute Schedule K1 if an automatic six-month extension was filed.
Calendar-year S corporations
September 15
Make contributions for 2024 to certain employer-sponsored retirement plans if an automatic six-month extension was filed.
September 15
File a 2024 income tax return (Form 1120-S) and provide each shareholder with a copy of Schedule K-1 (Form 1120S) or a substitute Schedule K-1 if an automatic six-month extension was filed. Pay any tax, interest and penalties due.
Calendar-year corporations
September 15
Pay the third installment of 2025 estimated income taxes, completing Form 1120-W for the corporation’s records.
Calendar-year trusts and estates
September 30
File a 2024 income tax return (Form 1041) if an automatic five-and-a-half-month extension was filed. Pay any tax, interest and penalties due.
October 2025
Individuals
October 10
Report September tip income of $20 or more to employers (Form 4070).
October 15
File a 2024 gift tax return (Form 709) and pay any tax, interest and penalties due if an automatic six-month extension was filed.
October 15
Make contributions for 2024 to certain existing retirement plans or establish and contribute to a SEP for 2024 if an automatic six-month extension was filed.
October 15
File a 2024 income tax return (Form 1040 or Form 1040-SR) if an automatic six-month extension was filed (or if an automatic four-month extension was filed by a taxpayer living outside the United States and Puerto Rico). Pay any tax, interest and penalties due.
Employers
October 15
Deposit nonpayroll withheld income tax for September if the monthly deposit rule applies.
October 15
Deposit Social Security, Medicare and withheld income taxes for September if the monthly deposit rule applies.
October 31
Report Social Security and Medicare taxes and income tax withholding for third quarter 2025 (Form 941) and pay any tax due if all of the associated taxes due weren’t deposited on time and in full.
Calendar-year C corporations
October 15
Make contributions for 2024 to certain employer-sponsored retirement plans if an automatic six-month extension was filed.
October 15
File a 2024 income tax return (Form 1120) if an automatic six-month extension was filed. Pay any tax, interest and penalties due.
Calendar-year bankruptcy estates
October 15
File a 2024 income tax return (Form 1041) if an automatic six-month extension was filed. Pay any tax, interest and penalties due.
November 2025
Individuals
November 10
Report October tip income of $20 or more to employers (Form 4070).
Employers
November 10
Report Social Security and Medicare taxes and income tax withholding for third quarter 2025 (Form 941) if all of the associated taxes due were deposited on time and in full.
November 17
Deposit nonpayroll withheld income tax for October if the monthly deposit rule applies.
November 17
Deposit Social Security, Medicare and withheld income taxes for October if the monthly deposit rule applies.
Calendar-year exempt organizations
November 17
File a 2024 information return (Form 990, Form 990-EZ or Form 990-PF) if a six-month extension was filed. Pay any tax, interest and penalties due.
December 2025
Individuals
December 10
Report November tip income of $20 or more to employers (Form 4070).
Employers
December 15
Deposit nonpayroll withheld income tax for November if the monthly deposit rule applies.
December 15
Deposit Social Security, Medicare and withheld income taxes for November if the monthly deposit rule applies.
Calendar-year corporations
December 15
Pay the fourth installment of 2025 estimated income taxes, completing Form 1120-W for the corporation’s records.
Track Federal & NY State Refunds
Wondering when your refund will arrive? Use these official tools to check the status:
Both tools provide up-to-date information so you can get answers faster.
Top Resources for Taxpayers
Skip the overwhelming IRS index and get direct links to the publications our clients find most useful:
Essential Tax Rates & Annual Updates
Stay informed with the most current federal tax brackets, deductions, and inflation adjustments, updated annually by the IRS. These trusted resources ensure you always have accurate numbers when planning your taxes—whether for personal returns or business decisions.
Have Questions About Your Taxes?
These tools are a great starting point, but personalized advice can save you time, money, and stress. Our team is here to help you interpret tax rules, meet deadlines, and plan for the future.