Ask L.A. County to Lower Your Property Assessment by Nov. 30

File Form RP-87 with the assessor if your home is worth less than its assessed value. A formal appeal costs $46.

You're wondering if it's too late to fight this year's property assessment in Los Angeles County. It isn't, but it will be after Monday, Nov. 30.

That night, two separate filings close. One is a Decline-in-Value Review, filed with the county assessor on Form RP-87. The other is a formal appeal, filed with a different county body, the Assessment Appeals Board. Assessor Jeff Prang's office laid out both in a guest column the Santa Monica Daily Press ran Nov. 6.

The review is for owners who think their property's market value on Jan. 1, 2026, was lower than its assessed value. Under Proposition 13, assessed value starts from a base year and generally can't rise more than 2% a year unless the property changes hands or gets new construction. Proposition 8, which voters passed in 1978, lets the assessor lower that value for a while when the market drops below it, the column explains.

Here's the review, in order:

1. Find two comparable sales. The assessor's office says the best evidence is two similar properties that sold as near to Jan. 1 as you can find, and no later than March 31.
2. Fill out Form RP-87, the Decline-in-Value Review Application. It's under the Forms tab on the assessor's Decline-in-Value webpage, and you can send it online.
3. Get it in by Nov. 30. Can't find comparable sales? File anyway. The office says it still accepts and processes applications that don't have them.
4. Let the appraiser decide. An appraiser goes through what you sent and may also look at other sales the office has on file. If your Jan. 1 market value comes in under what the office calls your trended base value, the Prop 13 figure it would otherwise use, your assessed value drops to market value for the fiscal year that began July 1. The lower number shows up on your annual tax bill. If market value comes in higher, nothing changes.

Here's the part people miss: the cut doesn't last. As prices recover, the assessor can raise the value back up, and the column warns that owners who got reductions in past years may see their taxes go up more than 2% in a year when values climb.

The formal appeal costs money. You file a Regular Assessment Appeal with the Los Angeles County Assessment Appeals Board, the county's quasi-judicial panel for value fights between owners and the assessor. It's due by midnight Pacific time on Nov. 30, you can file it online, and it covers both real and personal property.

The appeal fee is $46 and you won't get it back, according to the appeals board's site as of Nov. 9. The Board of Supervisors set the fee in 2021, and it's been charged since Oct. 1 of that year. You pay it when you submit. If paying it would be a real hardship, you can ask for a waiver, but the waiver form has to go in with your application. Paper copies are in Room B4 of the Kenneth Hahn Hall of Administration, 500 W. Temple St., downtown. The board's number is (213) 974-1471.

If fire or another disaster damaged your property, these probably aren't your forms. The appeals board's page points those owners to the assessor's disaster relief page and to relief@assessor.lacounty.gov.

Don't count on the grace rule, either. The assessor's office counts a mailed application as on time if it's postmarked the next business day when the deadline falls on a weekend or holiday. Nov. 30 is a Monday this year, so that rule won't apply.

Miss it, and both windows close. The board's regular appeal period doesn't open again until July 2.

Source: smdp.com, retrieved November 9, 2026. Other sources: Los Angeles County.