2016 estimate penalty calculation correction
The FTB has revised Form 5805, Underpayment of Estimated Tax by Individuals and Fiduciaries, to correct the penalty amount calculation. (FTB Public Service Bulletin (September 25, 2017)) The correction increased the penalty calculation multiplier from 0.0227 to 0.0239 (figures rounded). Taxpayers who filed this form before it was revised in May 2017 may have received a bill for an increased penalty amount. The form was originally published with an incorrect multiplier of 0.02269425. The revised form was uploaded to the FTB website on May 16, 2017, and tax preparation software companies were notified on May 22, 2017, so they could update their software.
Taxpayers who believe they were impacted by the correction should contact the FTB at:
Franchise Tax Board
P.O. Box 942840
Sacramento, CA 94240-0040