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With the 2018 filing season approaching, we have put together the following list of key tax-related deadlines affecting businesses and individuals. Below is a list of upcoming 2018 tax form deadlines to expect in the coming months:


  • S Corporations:
    File a 2017 calendar year income tax return (Form 1120S) and pay any tax due
  • S Corporation election:
    File Form 2553, Election by a Small Business Corporation, to elect to be treated as an S corporation beginning with calendar year 2017. If Form 2553 is filed late, S corporation treatment will begin with calendar year 2018.
  • Partnerships:
    File a 2017 calendar year return (Form 1065)
  • Electing larger partnerships:
    Provide each partner with a copy of Schedule K1 (Form 1065B), Partner’s Share of Income (Loss) From an Electing Large Partnership, or a substitute Schedule K1. This due date applies even if the partnership requests an extension of time to file the Form 1065B by filing Form 7004
  • Partnerships:
    Electing large partnerships: File a 2017 calendar year return (Form 1065-B)
  • Social security, Medicare, and withheld income tax:
    If the monthly deposit rule Page 6 Publication 509 applies, deposit the tax for payments in February. (If we process your payroll, we’re taking care of this each month.)


  • Electronic filing of Forms W2: 
    File copies of all the Forms W2 you issued for 2017. This due date applies only if you electronically file. (If we process your payroll, we’ve already filed these forms for you.)


  • Individual Tax Returns Due for Tax Year 2017:
    If you haven’t applied for an extension, e-file or postmark your individual tax returns by midnight April 18, 2018.
  • Individual Tax Return Extension Form Due for Tax Year 2017:
    Need more time to prepare your tax return? File your request for a tax extension by April 17 to push your tax deadline back to October 15, 2018.
  • 1st Quarter 2018 Estimated Tax Payment Due:
    If you are self-employed or have other first-quarter income that requires you to pay quarterly estimated taxes, get your Form 1040-ES postmarked by April 17, 2018 tax deadline.
  • Last Day to make a 2017 IRA Contribution:
    If you haven’t already funded your retirement account for 2017, do so by April 17, 2018. That’s the deadline for a contribution to a traditional IRA, deductible or not, and a Roth IRA. However, if you have a Keogh or SEP and you get a filing extension to October 15, 2018, you can wait until then to put 2017 money into those accounts.

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