Owning rental property in California can provide recurring income. Tax treatment also deserves close attention. The U.S. Census Bureau reports a median gross rent of $2,036 per month in California for 2020–2024, showing the scale of the state’s rental market.
Residential rental buildings generally use a 27.5-year federal recovery period. Cost segregation can identify qualifying components that belong in shorter recovery periods, potentially moving deductions into earlier years.
Understanding cost segregation in California
A cost segregation study in California separates qualifying property components into appropriate federal depreciation categories. Items such as certain appliances, carpeting, fixtures, landscaping improvements and fencing can qualify for shorter recovery periods. The study reallocates existing depreciable basis; it does not create a new deduction.
A worked first-year example
Consider a California investor who acquires a residential rental property for $2,400,000, of which $600,000 is allocated to land, leaving a depreciable building basis of $1,800,000. The investor separately purchases $80,000 of furniture, fixtures and equipment. The property is placed in service in January. Without a cost segregation study, the building is depreciated over 27.5 years and the first-year deduction under the mid-month convention is $62,730; the separately purchased FF&E receives 100% bonus depreciation of $80,000 whether or not a study is performed, for a total of $142,730. With a study, $216,000 is reclassified to five-year personal property and $180,000 to 15-year land improvements, giving $396,000 of accelerated basis eligible for 100% bonus depreciation. The remaining $1,404,000 stays on the 27.5-year schedule and produces $48,929 in year one. Adding the $80,000 of FF&E, the first-year deduction is $524,929. The study’s incremental contribution is $382,199, which at a 37% marginal federal rate defers roughly $141,414 of tax.
Passive activity limits
These deductions are not automatically usable. Under IRC Sec. 469, rental real estate is generally a passive activity and passive losses offset only passive income; unused losses are suspended and carried forward until the taxpayer has passive income or disposes of the activity in a fully taxable transaction. A taxpayer who qualifies as a real estate professional under Sec. 469(c)(7) and materially participates may treat the losses as non-passive. Separately, a rental with an average guest stay of seven days or less is not a rental activity under Reg. Sec. 1.469-1T(e)(3)(ii)(A), so material participation alone can make the losses non-passive without real estate professional status.
Current bonus depreciation rules
The bonus depreciation rules under IRC Sec. 168(k) determine how qualifying short-life assets can receive accelerated deductions.
The One Big Beautiful Bill Act (P.L. 119-21), signed July 4, 2025, made the 100% first-year bonus depreciation rate under IRC Sec. 168(k) permanent for qualifying property acquired and placed in service on or after January 20, 2025. Before that change the rate was phasing down on a fixed schedule of 80%, 60%, 40%, 20% and then 0%. Property acquired before January 20, 2025 remains subject to the phase-down percentage in effect at the time of acquisition.
Why California treatment is different
California does not conform to federal IRC 168(k) bonus depreciation. The Franchise Tax Board requires a separate California depreciation calculation, so federal and state bases need to be tracked independently. This can produce a faster federal deduction than the corresponding California deduction.
Your tax preparer should account for those differences when modeling the cash-flow benefit. The final result depends on the property, acquisition date, basis, classifications and your ability to use the deductions.
California also does not conform to IRC Sec. 469(c)(7), so for California purposes all rental activities remain passive regardless of real estate professional status.
Depreciation recapture
Accelerated depreciation is a deferral, not forgiveness. On a taxable sale, depreciation claimed on the five- and 15-year property a study reclassifies is recaptured under IRC Sec. 1245 as ordinary income to the extent of depreciation taken, potentially at rates up to 37%, rather than the 25% maximum applying to unrecaptured Sec. 1250 gain on the building itself. A study therefore shifts part of future gain from Sec. 1250 to Sec. 1245 treatment. The net benefit depends on the time value of the deferral and the expected holding period and is generally weaker for property expected to be sold within a few years.
Cost segregation can therefore be valuable for owners seeking earlier federal deductions. A qualified tax adviser can model the federal benefit alongside California’s separate treatment before you commission a study.
