California State 2012 Important Dates for Income Tax
When the due date falls on a weekend or holiday, the deadline to file and pay without penalty is extended to the next business day.
January 17, 2012
- Fourth quarter estimated tax due for 2011.
- State:
- Federal:
- 1040-ES (Instructions included)
March 15, 2012
- 2011 Corporation Income Tax returns due and tax due (for calendar year filers)
- State:
- 100 Booklet (Instructions included)
- 100S Booklet (Instructions included)
- Federal:
April 17, 2012*
- 2011 Personal Income Tax returns due and tax due
- State:
- 540/540A Booklet (Instructions included)
- 540 2EZ Booklet (Instructions included)
- 540NR Booklet (Instructions included)
- Federal:
2011 Partnership and LLC Income Tax returns due and tax due (for calendar year filers)
- State:
- 565 Partnership Booklet (Instructions included)
- 568 Limited Liability Company Tax Booklet (Instructions Included)
- Federal:
2012 first quarter estimated tax due for individuals and corporations
- State:
- Federal:
Due to the federal Emancipation Day holiday on April 16, 2012, tax returns filed and payments received on April 17, 2012, will be considered timely.
June 15, 2012
- 2012 second quarter estimated tax due for individuals and corporations
- State:
- 540-ES | Instructions
- 100-ES | Instructions
- 3536 Estimated Fee for LLCs (Instructions Included)
- Federal:1040-ES (Instructions included)
September 15, 2012
- 2012 third quarter estimated tax due for individuals and corporations
- State:
- Federal:
October 15, 2012
- Extended due date for 2011 Personal Income Tax returns
- State:
- 540/540A Booklet (Instructions included)
- 540 2EZ Booklet (Instructions included)
- 540NR Booklet (Instructions included)
- Federal:
Extended due date for 2011 Corporation Income Tax returns (for calendar year filers)
- State:
- 100 Booklet (Instructions included)
- 100S Booklet (Instructions included)
- Federal:
Extended due date for 2011 Partnership and LLC Income Tax returns (for calendar year filers)
- State:
- 565 Partnership Booklet (Instructions included)
- 568 Limited Liability Company Tax Booklet (Instructions Included)
- Federal:
December 17, 2012
- 2012 fourth quarter estimated tax due for corporations
- State:
January 15, 2013
- 2012 fourth quarter estimated tax due for individuals
- State:
- 540-ES | Instructions
- Federal:
- 1040-ES (Instructions included)

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