September is the last month of Q3, which means it’s right ahead of one of the busiest quarters of the year. Staying organized is key—and we’re here to help. Keep reading for key tax, payroll, and HR compliance dates this September.
Federal holidays
September 4, 2023
Labor Day
Monday, September 4 is Labor Day, so most businesses will be closed. Enjoy the day off!
Tax and payroll compliance deadlines
Payroll tax deposits (for semi-weekly depositors)
The Internal Revenue Service (IRS) requires employers who file Forms 940 and 941 to deposit payroll taxes at different frequencies throughout the year.
If you report more than $50,000 in payroll taxes during the lookback period of July 1, 2021 to June 30, 2022, you’re considered a semi-weekly depositor and must follow the schedule below:
| If payday for your employees is on… | Deposit employment taxes by… |
| Wednesday | The following Wednesday |
| Thursday | The following Wednesday |
| Friday | The following Wednesday |
| Saturday | The following Friday |
| Sunday | The following Friday |
| Monday | The following Friday |
| Tuesday | The following Friday |
However, if you accumulate $100,000 or more of tax liability in a single day, the IRS says you must deposit the amount by the following business day, regardless of whether you normally deposit on a semi-weekly or monthly basis (more on monthly deposits below).
To learn more about federal payroll tax deposits, read Publication 15.
Keep in mind that some state and local governments that collect payroll taxes will also expect their own deposits, and those deadlines may be different from the federal ones. For more information, contact your state and local tax agencies directly.
September 11, 2023
National Day of Service and Remembrance
Also called Patriot Day, the National Day of Service and Remembrance honors the people who lost their lives on September 11, 2001. Though Patriot Day is not technically a federal holiday, many individuals and businesses observe this day, taking time off to engage in community service or attend memorials.
Employee tip reporting deadline for August
Your employees are required to report to you any tips of $20 or more that they earned during the month of August. You can learn more about tip withholding and reporting requirements here. Employees use Form 4070.
September 15, 2023
Payroll tax deposits for monthly depositors
If your company follows the monthly payroll tax deposit schedule (meaning that you reported less than $50,000 in payroll taxes during the lookback period), then your tax deposit for August payrolls is due on September 15.
Estimated tax payment for Q3 due
If you make quarterly estimated tax payments, your third payment of the year is due September 15. You will likely make quarterly estimated tax payments if you fall into one of the following categories:
- C corporation
- S corporation shareholder
- Partnership
- Sole proprietor
- Independent contractors
- Freelancer
You can pay online, over the phone, or via mail using Form 1040-ES. For more information on estimated taxes, review Publication 505.
Form 8813 quarterly payment voucher due for partnerships
If you’re a partnership, you need to file Form 8813 by September 15 and pay any tax due. You can file the form at this address:
Internal Revenue Service Center
P.O. Box 409101
Ogden, UT 84409
For more information on Form 8813, see the IRS instructions here.
Form 1120-S extended filing deadlines for S-corps
If you own an S corporation (or if your LLC is taxed as an S corp), you’ll use Form 1120-S to report your income, losses, and dividends as a shareholder of the company. This form was due March 15. However, if you filed Form 7004 in March to request an automatic six-month extension, your deadline is now September 15.
Form 1065 extended filing deadlines for partnerships
If you own a partnership (or an LLC set up as a partnership), you’ll use Form 1065 to report the gains, losses, deductions, and credits of your operation. Keep in mind that each partner is responsible for paying their share of income from the business on their personal tax returns (Form 1040).
If you filed Form 7004 in March to request an automatic six-month extension, your deadline to file this form is September 15.
Estimated tax payment due for Q3 for tax-exempt organizations
If you own a tax-exempt organization (like a nonprofit) and expect your tax for the year to be more than $500, you need to pay any estimated tax on unrelated business income by September 15. You can use Form 990-W to calculate the amount of estimated tax required.
Forms 8804 and 8805 extended filing deadline for partnerships with accounts outside the US and Puerto Rico
If you’re a calendar-year partnership that keeps your business accounts and records outside of the US and Puerto Rico, you have to file Forms 8804 and 8805 to report your total tax liability. If you were granted a six-month filing extension, these forms are due September 15.
Form 1042 extended filing deadline
If you withhold taxes for international employees, you’re required to submit Form 1042 on an annual basis to report those withholdings. If you requested a six-month filing extension, the form is due September 15.
Learn more about Form 1042 from the IRS here.
September 30, 2023
End of Q3 for companies following the calendar year
If your company operates on a calendar year, the third quarter (Q3) ends on September 30.
HR compliance deadlines
September 15, 2023
Minimum funding contributions due for defined benefit plans
If your business has a defined benefit, money purchase, or target benefit plan that follows the calendar year, you must meet your minimum funding requirement for the 2022 plan year by September 15 to avoid excise taxes or operational failures.
That’s because plan sponsors are required to make any minimum contributions eight and a half months after the end of the plan year in question. Submit all electronic payments and mail all paper checks by September 15 to ensure your contributions are collected in a timely manner.
Deadline to make retirement plan employer contributions for partnerships and S corporations
If you’re a partnership or S corporation that filed an extension for your 2022 tax returns, the deadline to make any tax-deductible retirement plan employer contributions is September 15, the same day as the extended filing deadline.
September 30, 2023
Form 5500 due for certain plans
If your business offers pension or welfare benefit plans covered by The Employee Retirement Income Security Act of 1974 (ERISA), you’re required to file Form 5500 with the Employee Benefits Security Administration (EBSA). This form reports information about these plans, including its qualification, financial condition, operation, and investments.
Although Form 5500 is typically due on July 31, plan sponsors who qualify for an automatic corporate tax extension through Form 7004 may submit the document by September 30 through EFAST2 instead. For more information on Form 5500, see the Department of Labor’s detailed instructions.
Deadline to furnish Summary Annual Reports to covered plan participants
A Summary Annual Report (SAR) provides the information you submit in your Form 5500—including the total value of your company’s benefit plan during the previous plan year and other details—to your employees.
Since plan administrators must furnish this document to plan participants within nine months of the end of the plan year, the deadline to send SARs to your employees is September 30 (or two months after you file Form 5500) if you haven’t already filed for an extension with the IRS.
If you’ve successfully filed for an extension with Form 5558, your deadline for furnishing SARs to your employees is December 15.
Note that plans that don’t require you to file Form 5500 annually also don’t require SARs to be furnished to plan participants.
Remind employees to take advantage of their PTO and health benefits
The end of the calendar year is approaching fast, so it’s important to remind your employees about the benefits they’re entitled to. That includes any “use it or lose it” vacation days and sick days, as well as “use it or lose it” flexible spending accounts or health savings accounts.
It’s also a good time to encourage employees to get their annual flu shots, since flu season in the US starts in October.
