Outsourced ControllerA small business filing calendar for the whole year
You're looking for a small business filing calendar because you'd like to know which forms are due when, and who is supposed to file each one. Tax CFO Steven Palmieri leads the practice that keeps this calendar for owner-run companies, and Steven and his team put a name on every row. What follows is the federal year for a business on the calendar year, with who files each form and how we confirm it was done.
Write out my year
The federal dates, in one table
| Form | Who sends it in | Deadline | Our proof it went in |
|---|---|---|---|
| Quarterly payroll return (Form 941) | The provider | Last day of April, July, October and January | We match the provider's filing proof to the deposits |
| Annual unemployment return (Form 940) | The provider | January 31 | We check the filing receipt against the books |
| Employee wage statements (W-2) | The provider | January 31 | We check that the totals agree with payroll |
| Contractor payment forms (1099-NEC) | Whoever is assigned in writing | January 31 | We compare the vendor list to the forms filed |
| Owner's estimated tax installments | The owner, with amounts set by us | Mid April, mid June, mid September, mid January | We keep the payment record with the planning file |
| Returns for partnerships and S corporations | Prepared by our team | March 15 | We keep the filed copy and the acceptance |
| Returns for sole owners and C corporations | Prepared by our team | April 15 | We keep the filed copy and the acceptance |
A deadline that falls on a weekend or a public holiday rolls to the next working day. These dates assume a business on the calendar year.
Payroll returns first
The quarterly payroll return falls due at the end of the month that follows each quarter. For a calendar-year company, that means the last day of April, July, October and January. The annual Form 940 is due January 31. In most setups the payroll provider files both, and your job, or ours, is to check that they landed. Payroll checks after your provider runs payday goes into detail.
January is the busy month
W-2s and 1099-NEC forms are both due January 31. For payments made in 2026, the 1099-NEC reporting threshold is $2,000. That figure is stated for the year, and the IRS instructions are the place to check it each January. The reason January surprises owners is nearly always a missing vendor form, which is why bills, vendors and W-9s starts at the first payment.
Estimated taxes for the owner
Owners whose tax isn't withheld usually pay in four installments. Expect them around the middle of April, June, September and January. For corporations the pattern differs, and the IRS lists it in Publication 509. We set the amounts from closed months, so each installment is a number rather than a guess.
Business returns
Partnerships and S corporations on a calendar year file by March 15. C corporations and sole proprietors file by April 15. An extension moves the filing date but not the date a payment is due, so we plan payments ahead of the extension.
State dates, on your state's schedule
State sales tax returns and annual reports follow the calendar of the state where the business is registered and where it sells. They vary a good deal, so we list yours when we write out your year, and the page on selling into more than one state explains what drives them.
A look at the year as it unfolds
January carries the most. The year-end payroll forms and the vendor forms all come due, the fourth payroll return follows, and the last estimated installment is waiting for the owner. March is the month for partnership and S corporation returns. April brings the other business returns and the first estimate. Mid June and mid September each bring an estimate. The quarter-end payroll returns spread out through April, July and October.
Laid end to end, it looks busy. Laid out as a calendar, with the person responsible written beside each date, it looks manageable.
Who owns each line
The point of the table isn't the dates. The point is the second column. Most missed filings aren't missed by someone careless. They're missed because each person thought another one had it. We write a name next to every row.
On the calendar. The one recurring check this page adds is a first-of-the-month look at the next sixty days, so any date that's coming already has an owner and a note about what it needs.
A date that lands on a weekend is written on the next open business day, on that same line.