According to a 2016 report by the Small Business Administration (SBA), small businesses in the United States employ 56.8 million people and make up 99.7 of all businesses in the country. As such, small-business taxes have a significant role to play in the financial upkeep of these businesses.

As a small-business owner myself, I wanted to created a comprehensive go-to guide (complete with IRS-sourced information) that fellow business owners could use to plan for this tax year and years ahead.

Small-Business Taxes Deadlines by Month

Here are the critical filing deadlines for small-business taxes that must be met by all small businesses in 2017. Even though we're already approaching the second quarter of the year, you can keep these dates in mind for next year.

January

January 31: Non-employees must be sent their 1099 forms.

February

February 1: Deadline for sending copies of W2s out to your employees. Many payroll services can handle this automatically, but you may want to check so you know what role you'll need to play in ensuring that you meet the deadline.

March

March 15: S-Corporations must file their tax returns and pay any tax due. K-1s must be distributed to shareholders. Corporations can also request an automatic six-month extension to file their tax returns and issue K-1s using Form 7004. Partnerships must also file their tax returns and issue their partner K-1s. Partnerships can also request an automatic six-month extension to file their tax returns and issue K-1s using Form 7004. You can file the extension for S-Corporations and partnerships online.

March 15: Deadline for all businesses electing to be classified as an S-Corporation (Form 2553) starting in calendar year 2017. You may want to bookmark this form in case you are considering a future classification as an S-Corporation in future tax years.

March 31: Electronic filing deadline for businesses filing Forms 1097, 1098, 1099, 3921, 3922, and W-2G.

April

April 18: Deadline for C-Corporations to file their annual return (Form 1120) and pay taxes due. You can use Form 7004 to request an automatic 6-month extension. You can also file this extension online.

April 18: Corporations must make their first Estimated Tax Payment via Form 1120-W. 

June

June 15: Corporations must make their second Estimate Tax Payment via Form 1120-W. 

September

September 15: Partnerships that elected for an automatic 6-month extension must now file their 2016 tax returns via Form 1065, make payments due, and issue K-1s to all partners.

September 15: S-Corporations that elected for an automatic 6-month extension must now file their 2016 tax returns via Form 1120S, make payments due, and issue K-1s to all shareholders.

September 15: Corporations must make their third Estimate Tax Payment via Form 1120-W.

October

October 16: C-Corporations that elected for an extension must file their 2016 tax returns via Form 1120 and pay any taxes due.

December

December 16: Corporations must make their fourth Estimate Tax Payment via Form 1120-W. 

Other Dates to Keep in Mind for Small-Business Taxes

I recommend having these additional dates bookmarked to help you in this tax year (and tax years to come) with your small-business taxes:

• By December 31: Assemble data on all 1099 employees and prep to send to tax advisor or payroll service for timely issuance of 1099s by January 31 deadline. Many payroll services handle 1099s and W2s automatically. Be sure to know exactly what your payroll service handles and the dates on which you'll receive information for review and/or correction.
• By March 1: Decide whether you will file an automatic six-month extension and inform your tax advisor. Many advisors automatically file these forms for their business clients, so ask in advance whether your tax advisor does this as a regular course of business.
• Set reminders for April 1, June 1, September 1 and December 1. The 15th of each of these months are your estimated tax payment filing and payment deadlines. You don't want to miss them.

Also, don't ignore state deadlines. You may want to visit your state's Secretary of State website or Department of Revenue and bookmark critical state filing deadlines as well. You want to be sure you're filing in a timely fashion for all of your small-business taxes.

Need more help? You can check the IRS's 2017 Federal Tax Calendar.

Read more articles on taxes.

Photo: iStock

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