California imposes a progressive income tax with six rates, ranging from 1 percent to 12.3 percent. The state charges an additional 1 percent on taxable income of $1 million or more. Personal income tax has been the largest contributor to the state's general fund for years, comprising nearly 50 percent of revenue in recent years. The due date for filing California income tax is April 15. If you don't file your taxes on time, you will be charged a late payment penalty, as well as interest on the total of taxes due and possibly on the penalty.
How to File Late Tax Returns in California
Calculate the amount of income tax that you owe using your financial information. You may use one of the standard CA (540) forms or the worksheet provided on Form FTB 3519 to estimate your tax liability.
Pay the estimated amount of your tax liability by April 15 to avoid being charged a late payment penalty and interest. The penalty will be waived if you pay at least 90 percent of the tax by the due date. Form FTB 3519 offers four options for paying the tax: online payment, credit card, check or money order and through an installment agreement.
Mail your completed FTB 3519 to the address on the form only if you are paying by check or money order.
File your tax return by Oct. 15. The state gives you an automatic six-month extension, even if taxes were due. If you file after this date, you will be charged a late filing fee. If you do not owe taxes, no penalty is charged for filing late.
If you are traveling or living outside of the United States, the filing deadline is automatically extended to June 15. You will be charged interest on any taxes you owe, beginning on April 15, but you will not be charged a penalty. You will qualify for an addition six-month extension if you file by Dec. 15, but must pay any taxes that you owe by June 15 to avoid penalties. Attach a statement to the front of the return that explains that you were outside the United States.
If you have not filed taxes for one or more years or, for any reason, are unable to pay or file your state taxes, the state Franchise Tax Board encourages you to contact them for assistance.
The interest and penalties on late tax payments can be substantial. You can be charged an underpayment penalty of up to 25 percent of the unpaid tax for paying late. You risk up to an additional 25 percent delinquent penalty for both paying and filing late. The state charges interest on the unpaid tax starting on the date the tax was due and interest on any penalties if they are not paid within 15 days of receiving the billing notice.
Things You'll Need
California form FTB 3519
California form 540