How California High Earners Use Bonus Depreciation and Cost Segregation to Reduce Taxes

Real estate can be one of the most powerful tax planning tools available to high-income earners. But the strategy is often misunderstood.

Many people hear that they can buy a rental property, complete a cost segregation study, claim bonus depreciation, create a large paper loss, and use that loss to offset W-2 income, RSU income, or business income.

Sometimes that is true. Often, it is not.

For high-income Californians, this planning can be especially valuable, but it is also more complex. Federal tax law may allow accelerated depreciation, but California does not fully follow the federal bonus depreciation rules. That means a real estate investment can create large federal deductions while producing smaller or slower deductions for California purposes.

The result: bonus depreciation and cost segregation can work, but only when the real estate investment, passive activity rules, California tax rules, documentation, and exit strategy all fit together.

Why High-Income Californians Care About Bonus Depreciation

High-income Californians often face a heavy combined federal and state tax burden. A tech executive, founder, physician, attorney, consultant, or business owner may have income from:

• W-2 wages
• RSUs
• ISOs or NSOs
• ESPP shares
• business income
• capital gains
• rental income
• portfolio income

For these taxpayers, deductions that can offset ordinary income may be valuable.

Real estate depreciation is attractive because it can create tax deductions without requiring an equivalent cash outlay in the same year. A property may be cash-flow positive before principal payments and taxes but still show a tax loss because depreciation reduces taxable income.

This is why depreciation is often called a paper loss.

But the key question is not simply whether the property creates a paper loss. The key question is whether that loss is passive or nonpassive.

What Is Depreciation?

Depreciation is a tax deduction that allows a property owner to recover the cost of certain assets over time.

For residential rental real estate, the building is generally depreciated over 27.5 years for federal tax purposes. Commercial real estate is generally depreciated over 39 years. Land is not depreciable.

For example, if you buy a rental property for $2 million and $1.4 million is allocated to the building, the building portion may be depreciated over 27.5 years if it is residential rental property.

That creates annual depreciation deductions even if the property is increasing in market value.

What Is Bonus Depreciation?

Bonus depreciation allows taxpayers to deduct a large percentage of the cost of certain qualified property in the year it is placed in service.

For real estate investors, bonus depreciation usually does not apply to the main building structure. Instead, it may apply to shorter-life property components identified through a cost segregation study.

Examples may include:

• appliances
• furniture
• carpet and certain flooring
• decorative lighting
• certain cabinetry or removable fixtures
• equipment
• site improvements
• landscaping
• fencing
• paving
• exterior lighting
• certain specialty electrical or plumbing components

Under current federal guidance, qualified property acquired and placed in service after January 19, 2025 may qualify for 100% bonus depreciation.

That creates a major timing benefit: instead of depreciating certain components over 5, 7, or 15 years, the taxpayer may be able to deduct them immediately for federal tax purposes.

What Is a Cost Segregation Study?

A cost segregation study is an engineering-based tax analysis that breaks a property into different depreciable components.

Instead of treating most of the property as one 27.5-year or 39-year asset, the study identifies components that may qualify for shorter depreciation periods.

The shorter-life components are where bonus depreciation may create large upfront federal deductions.

A qualified study can also help support the taxpayer's position if the depreciation classifications are later questioned. For larger or more complex properties, an engineering-based study is generally more defensible than a rough estimate.

How Cost Segregation and Bonus Depreciation Create Paper Losses

Assume a California high-income earner buys a furnished short-term rental property for $2 million.

After allocating part of the purchase price to land, assume $1.5 million is depreciable. A cost segregation study identifies $450,000 of shorter-life assets that qualify for 100% federal bonus depreciation.

Economically, the property may be close to break-even or even positive before principal payments and taxes. But for federal tax purposes, it may show a large loss because of accelerated depreciation.

That loss may be valuable if it can offset other income. But whether it can offset W-2 income, RSU income, or business income depends on the passive activity rules.

The Passive Activity Loss Problem

This is where many real estate tax strategies get oversold. Under federal tax rules, rental real estate activities are generally passive. Passive losses generally can offset passive income, but they usually cannot offset wages, business income, or portfolio income.

For high-income earners, the common $25,000 rental real estate loss allowance is usually not available because it phases out as income rises.

So a high-income Californian who buys a long-term rental and hires a property manager may generate a large passive loss that does not currently offset W-2 income. Instead, the loss may be suspended and carried forward.

That does not mean the loss is worthless. Suspended passive losses may offset future passive income or may be released in a qualifying taxable disposition. But they may not reduce this year's tax bill from salary, RSUs, or business income.

The Two Main Paths to Using Real Estate Paper Losses Against High Income

1. Real Estate Professional Status

Real Estate Professional Status, often called REPS, can allow rental real estate losses to be treated as nonpassive if the taxpayer qualifies and materially participates.

A taxpayer generally must satisfy two tests:

• perform more than 750 hours of services during the year in real property trades or businesses in which the taxpayer materially participates
• perform more than half of all personal services during the year in real property trades or businesses in which the taxpayer materially participates

For married couples filing jointly, one spouse may qualify even if the other spouse has high W-2 income. This is why REPS is often most relevant for households where one spouse has a high-paying job and the other spouse spends substantial time in real estate.

REPS is difficult for a full-time W-2 employee to claim personally because the more than half test is hard to satisfy while working a full-time non-real-estate job.

Even if REPS is satisfied, the taxpayer must also materially participate in the rental activities. A grouping election may also be relevant, depending on the facts.

2. Short-Term Rental Material Participation

Short-term rentals may provide a different path.

For passive activity purposes, an activity involving use of tangible property is generally not treated as a rental activity if the average customer use is seven days or less. This is why short-term rentals are often discussed in high-income tax planning.

If the short-term rental is not treated as a rental activity under these rules, and the taxpayer materially participates, the resulting loss may be nonpassive even if the taxpayer does not qualify as a real estate professional.

This can be attractive for high-income professionals who cannot meet REPS because they have full-time jobs.

But the rules are technical. The taxpayer generally needs to monitor:

• average guest stay
• material participation
• time logs
• whether anyone else spends more time than the owner
• third-party property manager involvement
• personal use
• services provided to guests
• local short-term rental restrictions
• platform records
• cleaning, maintenance, and guest communication records

The short-term rental strategy can work, but it requires real operational involvement and careful documentation.

REPS vs. Short-Term Rental Strategy

Why Full-Time W-2 Earners Often Struggle With REPS

This point is important for California tech employees and executives. A full-time W-2 employee often works 1,800 to 2,500 hours per year in a non-real-estate job. To qualify personally for REPS, more than half of all personal services must be in real property trades or businesses.

That can be difficult or impossible if the taxpayer is working full-time in technology, medicine, law, finance, or another non-real-estate profession.

This is why the REPS spouse structure is common: one spouse earns high W-2 income while the other spouse genuinely spends substantial time in real estate and meets the REPS tests.

But the facts must support the claim. Documentation matters.

Material Participation: Documentation Is Critical

For REPS or short-term rental strategies, documentation is often the difference between a defensible tax position and a risky one.

Taxpayers should maintain:

• contemporaneous time logs
• calendar entries
• emails and messages
• guest communication records
• vendor coordination records
• maintenance records
• bookkeeping records
• travel records
• renovation records
• property management records
• platform reports
• notes on acquisition, financing, repairs, and operations

Reconstructing time logs after the fact is weaker than maintaining records throughout the year.

California Does Not Conform to Federal Bonus Depreciation

This is the most important California-specific issue. California does not conform to federal bonus depreciation under IRC Section 168(k). The Franchise Tax Board states that California personal income tax law specifically does not conform to bonus depreciation.

That means a California taxpayer may need to maintain two depreciation schedules:

The practical effect is simple: a property may create a large federal loss but a much smaller California loss.

Example: Federal vs. California Tax Treatment

Assume a cost segregation study identifies $450,000 of assets eligible for federal bonus depreciation. For federal purposes, the taxpayer may deduct the full $450,000 in year one.

For California purposes, the taxpayer generally does not get the same upfront deduction. Instead, those assets may be depreciated over the applicable California recovery periods.

This does not necessarily mean California permanently denies the deduction. Often, the issue is timing. California may allow depreciation over future years, but not as a large upfront bonus deduction.

That timing difference can materially reduce the state-tax benefit in year one.

Why Two Depreciation Schedules Matter

Maintaining separate federal and California depreciation schedules is not just an accounting detail. It affects:

• annual taxable income
• estimated tax payments
• federal vs. California tax projections
• basis tracking
• future gain or loss calculations
• depreciation recapture
• sale projections
• 1031 exchange planning
• estate planning
• multi-state tax reporting
• CPA preparation costs

For California residents, this strategy is not set it and forget it. The recordkeeping burden is part of the planning.

Bonus Depreciation Is Often Tax Deferral, Not Tax Elimination

Bonus depreciation can reduce current federal taxable income, but it often shifts tax consequences into the future. When you sell the property, prior depreciation deductions can increase taxable gain because depreciation reduces tax basis.

This is why bonus depreciation should be analyzed across the full investment lifecycle, not just the year-one tax result.

Depreciation Recapture: What Happens When You Sell?

Depreciation recapture is the tax system's way of accounting for depreciation deductions when an asset is sold.

In simplified terms:

• Depreciation on certain personal property components may be recaptured as ordinary income.
• Depreciation on real property may be taxed under unrecaptured Section 1250 gain rules.
• Additional gain may be taxed as capital gain.
• California may calculate gain differently because its depreciation schedule may differ from the federal schedule.

If the property is sold, the lower adjusted basis can increase taxable gain. That does not mean depreciation was a bad strategy. It may have provided valuable tax deferral and improved after-tax cash flow. But it means the exit plan matters.

Three Exit Paths: Sell, Exchange, or Hold

1. Sell the Property

Selling may trigger depreciation recapture, capital gains, and California tax. Because California and federal depreciation schedules may differ, the gain calculation can also differ.

2. Use a 1031 Exchange

A 1031 exchange may allow an investor to defer gain and depreciation recapture by exchanging into another like-kind investment property. The gain is deferred, not eliminated. Basis carries over into the replacement property.

California generally conforms to 1031 exchange treatment, but California has tracking and reporting rules when California property is exchanged for out-of-state replacement property.

3. Hold Until Death

Under current law, heirs may receive a step-up in basis when they inherit appreciated property. This may reduce or eliminate built-in capital gain and depreciation recapture. That is why some long-term real estate investors prefer to hold appreciated property indefinitely rather than sell.

However, this strategy has risks:

• Tax law can change.
• Debt can increase financial risk.
• Properties may underperform.
• Liquidity may be limited.
• Estate tax may apply for very large estates.
• Heirs may not want to manage the property.
• California and federal rules may not always produce identical results.

The step-up in basis is powerful, but it should not be the only reason to buy a property.

What Types of Properties May Benefit Most?

Cost segregation and bonus depreciation may be more useful when a property has a meaningful amount of shorter-life assets.

Examples include:

• furnished short-term rentals
• multifamily properties with appliances and land improvements
• commercial properties with specialized buildouts
• medical or dental office buildings
• hospitality properties
• self-storage facilities
• mobile home parks
• properties with substantial exterior improvements
• properties undergoing renovation or improvement

A plain long-term single-family rental may still benefit from cost segregation, but the result may be less dramatic than a furnished short-term rental or a property with significant land improvements.

At-Risk Rules Still Matter

Even if the taxpayer clears the passive activity rules, the at-risk rules may still limit deductions.

In general, taxpayers can deduct losses only to the extent they are economically at risk. Debt structure matters. Recourse debt, qualified nonrecourse financing, guarantees, and related-party financing can affect whether losses are currently deductible.

A real estate tax strategy should be reviewed for both passive activity limitations and at-risk limitations.

Common Mistakes High-Income Earners Make

1. Assuming Every Rental Loss Offsets W-2 Income

Most rental losses are passive. High-income taxpayers often cannot use passive rental losses against wages unless they qualify under REPS, short-term rental material participation, or another exception.

2. Buying a Property Only for the Tax Deduction

A deduction does not fix a bad investment. The property should make sense after considering price, financing, location, cash flow, insurance, repairs, local regulation, management burden, and exit options.

3. Ignoring California Nonconformity

Federal bonus depreciation may create a large federal deduction, but California may not allow the same deduction upfront. This can create unexpected state tax liability.

4. Forgetting Depreciation Recapture

Accelerated depreciation can reduce taxes today but increase taxable gain later.

5. Overlooking Personal Use Rules

This is especially important for short-term rentals.

6. Outsourcing Too Much Management

For short-term rental material participation, using a full-service property manager may make it harder to show that the owner materially participated.

7. Poor Time Tracking

REPS and material participation are fact-intensive. Vague estimates are risky.

8. Not Modeling the Exit

The sale, 1031 exchange, refinance, or hold-until-death strategy should be modeled before the property is purchased.

Who Is This Strategy Best For?

Bonus depreciation and cost segregation may be most useful for:

• high-income W-2 earners with a spouse who can qualify for REPS
• business owners with flexibility to materially participate in real estate
• tech employees with large RSU income who actively manage a qualifying short-term rental
• founders expecting a high-income year or liquidity event
• real estate investors with passive income from other properties
• families building long-term real estate portfolios
• taxpayers with large capital gains who want real estate exposure
• investors willing to hold property long term

It may be less appropriate for:

• taxpayers who want a completely passive investment
• people unwilling to maintain documentation
• investors relying on aggressive tax assumptions
• buyers purchasing overpriced properties solely for deductions
• California taxpayers who have not modeled the state tax impact
• people who may need to sell quickly

A Practical Planning Framework

Before using bonus depreciation and cost segregation as a tax strategy, high-income Californians should answer seven questions.

1. Will the property qualify for meaningful accelerated depreciation?

A cost segregation estimate can help determine whether the potential deduction justifies the cost and complexity.

2. Will the losses be passive or nonpassive?

This is the most important tax question. A large passive loss may not reduce current W-2 or RSU income.

3. Can you qualify under REPS or short-term rental material participation?

The answer depends on facts, time, documentation, and how the property is operated.

4. Can you document your position?

Time logs, calendars, guest records, vendor records, and operational involvement matter.

5. What is the California tax result?

Federal savings may be much larger than California savings because California does not conform to bonus depreciation.

6. What happens when you sell, exchange, or hold?

Model depreciation recapture, capital gain, California tax, 1031 exchange options, and step-up in basis.

7. Does the investment make sense without the tax benefit?

The property should be financially sound even if the tax benefit is delayed, limited, or challenged.

Examples

High-Income California Tech Employee

Assume a California tech employee has $900,000 of W-2 and RSU income. They buy a furnished short-term rental and materially participate in the activity. A cost segregation study identifies $350,000 of property eligible for federal bonus depreciation.

If the short-term rental rules are satisfied and the taxpayer materially participates, the resulting loss may be nonpassive and may offset W-2 income for federal purposes.

But for California purposes, the full $350,000 bonus depreciation deduction may not be available upfront. The taxpayer may still owe significant California tax because California does not conform to federal bonus depreciation.

Married Couple Using REPS

Assume one spouse earns $1.2 million from W-2 income and RSUs. The other spouse works substantially in real estate, meets the 750-hour and more-than-half tests, and materially participates in the couple's rental real estate activities.

The couple purchases a rental property, completes a cost segregation study, and generates a large federal depreciation loss. If the REPS and material participation rules are satisfied, the rental loss may be nonpassive and may offset the high-earning spouse's income on the joint federal return.

Again, California must be modeled separately because federal bonus depreciation and California depreciation may differ.

Passive Investor With No REPS

Assume a high-income California physician buys a long-term rental property and hires a property manager. A cost segregation study creates a $250,000 federal loss.

Because the rental activity is passive and the taxpayer does not qualify for REPS, the loss may be suspended. It may offset passive income in future years or be released on a qualifying disposition, but it may not reduce the physician's current W-2 income.

The cost segregation study may still be useful, but it does not create the immediate tax result the taxpayer expected.

Final Thoughts

Bonus depreciation and cost segregation can be powerful tools for high-income Californians, but they are not magic.

The real opportunity comes from combining:

• a sound real estate investment
• a properly prepared cost segregation study
• federal bonus depreciation
• careful passive activity planning
• REPS or short-term rental material participation, where appropriate
• California depreciation tracking
• at-risk rule analysis
• recapture, 1031 exchange, and step-up planning
• strong documentation

For California residents, the federal tax benefit can be much larger than the state tax benefit because California does not conform to federal bonus depreciation. That makes planning more complex, not less.

Used correctly, bonus depreciation may accelerate deductions, improve after-tax cash flow, and help offset high-income years. Used carelessly, it can create suspended losses, California tax surprises, recapture issues, and audit risk.

The best strategy is not simply to buy real estate for tax savings. It is to build a coordinated plan where the investment, tax rules, cash flow, documentation, and exit strategy all work together.