In California, there are two different filing deadlines for challenging annual local property tax assessments. Depending on where the property is located, the deadline is either September 15 or November 30 (except when those dates fall on a weekend or holiday, in which case the deadline generally is extended to the next business day).
In order for a county to impose the September 15 deadline, it must separately inform each assessee of the value that the assessor has placed on the roll for the taxpayer's property. However, because most counties reasonably do not wish to expend the effort or funds to send out this notice, they simply adopt the later filing deadline of November 30.
Nevertheless, there are a handful of counties that do incur the extra cost to send out those notices, primarily in order to shorten the time for taxpayers to file an appeal. This year, the following counties have a deadline of September 15, 2011:
San Luis Obispo*
*These counties also have filing fees/deposits that must be paid in order to lodge an appeal with the assessment appeals board. Approximately half of the counties with a November 30 deadline also have filing fees.
Keep in mind that each county has a different assessment appeal application and that the deadlines referenced above relate only to annual assessment appeals. Other assessments, such as supplemental and escape assessments, have different deadlines based on when the notices and/or bills relating to them are issued.