If you claimed exemption from income tax withholding last year on the Form W-4, Employee's Withholding Allowance Certificate, you gave your employer, you must file a new Form W-4 by this date to continue your exemption for another year
Give annual information statements to recipients of certain payments you made during 2017.
File information returns (for example, certain Forms 1099) for certain payments you made during 2017.
Farmers and fishermen
File your 2017 income tax return (Form 1040) and pay any tax due.
Employees who work for tips
If you received $20 or more in tips during February, report them to your employer.
File a 2017 calendar year return (Form 1065).
Electing large partnerships
File a 2017 calendar year return (Form 1065-B).
File a 2017 calendar year income tax return (Form 1120S) and pay any tax due.
S corporation election
File Form 2553 to elect to be treated as an S corporation beginning with calendar year 2018.