September 17, 2018 @ 12:00 am - September 18, 2018 @ 12:00 am Corporations: Deposit the third installment of your 2018 estimated tax.
September 17, 2018 @ 12:00 am - September 18, 2018 @ 12:00 am Electing Large Partnerships: File Form 1065-B if you timely requested a 6-month extension.
September 17, 2018 @ 12:00 am - September 18, 2018 @ 12:00 am Individuals: Pay the third installment of your 2018 estimated tax – Use Form 1040-ES.
September 17, 2018 @ 12:00 am - September 18, 2018 @ 12:00 am Partnerships: File calendar year Form 1065 if you timely requested a 6-month extension.
September 17, 2018 @ 12:00 am - September 18, 2018 @ 12:00 am Corporations: File calendar year Form 1120S if you timely requested a 6-month extension.