You may file Form 1040, Form 1040A or Form 1040EZ any time before the six-month extension period ends. You must make a proper estimate of your tax for the year.We automatically allow a 7-month extension for businesses to file Form 100 (coming soon) that are not suspended. This includes exempt organizations. This gives you until October 15 to file without penalties. You can get an automatic 6-month State of California tax extension and have until October 15 to file your return. California offers a 6-month extension, which moves the filing deadline to October 15 (for calendar year filers). California will – under limited circumstances – allow you to request a 30-day sales tax filing extension. You'll receive an electronic acknowledgment once you. California automatically grants an extension of time to file.