P.L. 115-97 replaced the graduated corporate tax structure with a flat 21% corporate tax rate, effective for tax years beginning after December 31, 2017. Therefore, the maximum tax rate for corporations has decreased from 35% to 21%. However, under section 15, corporations and section 1446 partnerships with fiscal tax years beginning before January 1, 2018, and ending after December 31, 2017, figure their tax by blending the corporate rates in effect before January 1, 2018, with the rate in effect after December 31, 2017. For more information see the Instructions for Form 1120, available at IRS.gov/Form1120, and other impacted forms and instructions posted on or after April 13, 2018, and available at IRS.gov/DownloadForms. More information is available in Notice 2018-38.
Below is a list of impacted forms and instructions.
Instructions for Form 990-T
Form 990-W (2017) (PDF)
Instructions for Form 1120
Instructions for Form 1120-C
Instructions for Form 1120-F
Instructions for Form 1120-L
Instructions for Form 1120-PC
Form 1120-POL
Instructions for Form 1120-REIT
Form and Instructions 1120-RIC
Instructions for Form 1120-S
Form and Instructions 1120-S Sch D
Instructions for Form 1120-W
Form 2438
Instructions for Form 4720
Form and Instructions 6765
Form and Instructions 8804
Form and Instructions 8804- Sch A
Form 8804-W
Form 8831
Form and Instructions 8902