2019 Q3 Tax Calendar: Key Deadlines for Businesses and Other Employers


key deadlines q3 2019

Here are some of the key deadlines Q3 2019 affecting businesses and other employers. Keep in mind that this list isn’t all-inclusive, so there may be additional deadlines that apply to you. Contact our accounting firm to ensure you’re meeting all applicable deadlines and to learn more about the filing requirements.

Key Deadlines Q3 2019

July 31
– Report income tax withholding and FICA taxes for the second quarter of 2019 (Form 941) and pay any tax due. (See the exception below, under “August 12.”)

– File a 2018 calendar-year retirement plan report (Form 5500 or Form 5500-EZ) or request an extension.

August 12
– Report income tax withholding and FICA taxes for the second quarter of 2019 (Form 941), if you deposited on time and in full all of the associated taxes due.

September 16

Here is the final set of key deadlines for Q3 2018.


– If a calendar-year C corporation, pay the third installment of 2019 estimated income taxes.

– If a calendar-year S corporation or partnership that filed an automatic six-month extension:

– File a 2018 income tax return (Form 1120S, Form 1065 or Form 1065-B) and pay any tax, interest and penalties due.

– Make contributions for 2018 to certain employer-sponsored retirement plans.

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