If you own rental properties, you’ve probably heard that depreciation is one of the best tax tools available to real estate investors. But here’s the honest truth many investors miss: depreciation works only if you understand the mechanics, claim it correctly, and know when cost segregation might accelerate your deductions. This guide walks you through how depreciation actually works, why cost segregation exists, and whether it makes sense for your portfolio.
How Depreciation Works on Rental Property
Depreciation is a non-cash paper loss that lets you deduct a portion of your property’s value each year without spending money. Here’s how it actually functions.
Land Never Depreciates; Only the Building Does
This is the foundation rule. When you buy a rental property, the purchase price is split between the land and the building. The IRS lets you deduct the building over time, but land is considered a permanent asset that never wears out, so it has zero depreciation.
In practice, you need to figure out what portion of your purchase price is land versus building. Most investors use county assessment records (the assessor typically shows a land value and an improvement value) or hire an appraiser to split the price. Land is often roughly 15 to 25 percent of total value, but this varies by market.
Key takeaway: accurately split land from building on day one, or you will depreciate too much and face recapture headaches later.
The Two Main Depreciation Schedules: 27.5 Years and 39 Years
Residential rentals (apartments, single family rentals you rent to tenants) depreciate over 27.5 years. Commercial properties and short term rentals depreciate over 39 years. This is the normal recovery period under current tax law.
The difference matters. A 27.5 year rental life produces a larger annual deduction than a 39 year schedule on the same building value. If you own a short term rental (also called an STR, or a property rented on Airbnb or VRBO) that is used on a transient basis (a hotel/motel-type use, where more than half the units are rented to transient guests), it generally falls under the 39 year nonresidential schedule, not the 27.5 year residential schedule, because a transient unit is not treated as a “dwelling unit.”
Key takeaway: check your property type to confirm which schedule applies, because it directly affects your annual deduction.
When Depreciation Starts: Placed-in-Service Date
Depreciation does not start on the date you purchase the property. It starts when the property is placed in service, meaning it is ready and available for rent to tenants. This is often called the placed-in-service date.
For example, imagine you bought a rental property in December 2025. You renovated it and finished the work in February 2026, when you listed it for rent. Depreciation begins February 2026, not December 2025. If you bought it and it was already rented out, the placed-in-service date might be the purchase date itself.
This timing affects your first year deduction. A property placed in service partway through the year gets a partial year of depreciation in year one.
Key takeaway: track the placed-in-service date carefully, because it determines when your deductions begin.
Depreciation Is Not Optional, and Form 3115 Catches Up Missed Years
Here is something that surprises many investors: depreciation is not optional. The IRS assumes you took all allowable depreciation, whether or not you actually claimed it on your return. This creates a problem if you failed to claim depreciation in prior years.
Why does this matter? Years from now, if you sell the property, you will owe depreciation recapture tax on all the years you should have claimed depreciation, even if you did not. You pay tax on something you never deducted, which is doubly unfair.
The solution is IRS Form 3115, which is a request to change your accounting method. You can use it to catch up missed depreciation from prior years in one shot, often without amending every single prior year return. This is one of those tax law details that saves investors thousands when they find out about it early.
Key takeaway: if you never claimed depreciation on a property, file Form 3115 now to catch up, and stop the clock on recapture.
Cost Segregation: Reclassifying Components Into Shorter Lives
Now we move into a more advanced strategy that pairs with depreciation to accelerate your deductions even further. This is cost segregation.
What Cost Segregation Does
Cost segregation is a reclassification strategy. It takes components of your property (things like flooring, appliances, fixtures, electrical systems, and certain land improvements) and sorts them into shorter depreciation lives, such as 5 years, 7 years, or 15 years, rather than depreciating the whole building over 27.5 or 39 years.
This does not change the total deduction you get over the life of the property. It front-loads it. Instead of spreading depreciation evenly over 27.5 years, cost segregation bunches a lot of depreciation into the first few years.
A cost segregation study is usually performed by engineers and accountants who inspect the property, break down the components, and prepare a detailed report. The cost of a study ranges from roughly $2,000 to $4,000 for a single family rental, depending on complexity and the appraiser’s location.
Key takeaway: cost seg accelerates deductions into the near term, not increases them over time. It is valuable only if you can use the losses now.
Bonus Depreciation and OBBBA
The One Big Beautiful Bill Act (OBBBA), signed July 4, 2025, restored 100 percent bonus depreciation permanently for qualifying property that is acquired and placed in service after January 19, 2025. Bonus depreciation applies to property with a recovery period of 20 years or less, so it does not cover the building shell (27.5 or 39 year real property), but it does cover the 5, 7, and 15 year components a cost segregation study identifies. It lets you deduct a large portion or even all of that cost segregation property in year one instead of over 5, 7, or 15 years. (Property placed in service on or before January 19, 2025 uses the older phase-down percentage: 80 percent for 2023, 60 percent for 2024, and 40 percent for early 2025.)
When you combine a cost segregation study with 100 percent bonus depreciation, you can create very large deductions in the purchase year. This is particularly powerful for large properties or portfolios where the up-front deduction can offset significant income.
Here is a real example from my multifamily practice. I was a general partner on a 106 unit apartment community acquired in 2023. Without cost seg, the annual depreciation would have been roughly $100,000 per year. We completed a cost segregation study and applied bonus depreciation (80 percent for property placed in service in 2023) to qualifying components, and the result was a deduction of more than $1,000,000 in the first year alone. Because the deal is held in a partnership, that deduction passed through to the partners and, for those able to use it, sheltered a substantial amount of income.
This is the power of cost seg combined with bonus depreciation. But it only works if you have the income to absorb the deduction, which brings us back to the core question: who should use this strategy?
Key takeaway: bonus depreciation plus cost seg can create six-figure deductions in year one, but only for properties large enough and owners with enough income to justify the cost.
Cost Segregation on Properties You Have Owned for Years
One myth about cost segregation is that you can only do it on a property you just purchased. This is false. You can perform a cost segregation study on a property you bought years ago and use Form 3115 (the same form we discussed for missed depreciation) to catch up the reclassified depreciation in prior years.
This opens a door for investors with older properties in their portfolio. If you have owned a rental for five or ten years and never done a cost seg study, you can still do one now, catch up the reclassified amounts, and accelerate those deductions even in the current year.
Key takeaway: cost segregation is not just for new acquisitions. Older properties can benefit if the numbers work.
When Is Cost Segregation Worth the Cost?
This is the practical question every investor faces. You are considering a $2,000 to $4,000 study fee. Will it pay off?
Cost segregation shines for two groups of investors: short term rental operators and Real Estate Professionals (REPS) who can use depreciation losses against active income like W-2 wages. Here is why.
If you have suspended passive losses (losses you could not use because you are not a REPS and your income is too high), a cost seg study will create more losses that simply sit in suspension alongside the ones you already have. The study cost does not pay off because you cannot use the deductions now.
But if you are a REPS or an STR operator with material participation (topics we cover in depth in our guide on real estate professional status and the short term rental loophole), those cost seg deductions offset active income immediately. The $2,000 study that produces $30,000 or $40,000 in deductions saves you roughly $8,000 to $10,000 in taxes at a 25 to 30 percent tax rate. That is a strong return on the investment.
Real examples from my practice illustrate this. I worked with a short term rental client who bought a property in 2025 (placed in service after January 19, so it qualified for 100 percent bonus) for $420,000 and made $45,000 in improvements, creating a depreciable basis of roughly $348,000 after removing land value. A cost seg study identified that about 40 percent of the basis qualified for bonus depreciation, producing roughly $139,000 in accelerated depreciation. At a 24 percent tax rate, that translated to roughly $32,000 in tax savings. The study fee was easily justified.
Compare that to an investor with suspended passive losses from other rentals. Cost seg creates more losses, but those losses sit unused because the investor is not a REPS and income is too high to use them under the special $25,000 allowance. The study fee is a sunk cost.
Key takeaway: cost segregation makes financial sense for STR operators and REPS investors who can use losses immediately, not for owners with already suspended passive losses.
Link Down to Deeper Strategy Articles
Each of the topics above is worth exploring in depth:
- How Depreciation Works: Learn the full mechanics of calculating depreciation, the placed-in-service rule, and how it flows into your tax return. (link placeholder: /how-depreciation-works/)
- Common Depreciation Mistakes: The most frequent errors rental owners make with depreciation, and how to avoid them. (link placeholder: /common-depreciation-mistakes/)
- What Is Cost Segregation: A complete walkthrough of the cost segregation process, what engineers study, and how the report is used. (link placeholder: /what-is-cost-segregation/)
- Bonus Depreciation and OBBBA: How the One Big Beautiful Bill Act restored 100 percent bonus depreciation and what it means for your deals. (link placeholder: /bonus-depreciation-obbba/)
- Cost Segregation on Old Properties: How to use Form 3115 to catch up cost seg on properties you have owned for years. (link placeholder: /cost-segregation-on-old-property/)
- Is Cost Segregation Worth It: A detailed cost-benefit analysis for single family rentals and small portfolios. (link placeholder: /is-cost-segregation-worth-it/)
Frequently Asked Questions
When does depreciation start on my rental, at purchase or when it is rented?
Depreciation starts when the property is placed in service, meaning it is ready and available for rent. If you buy a property and it is already rented, the placed-in-service date might be close to the purchase date. If you buy it vacant and renovate it, depreciation starts when renovation is finished and you list it for rent. Track this date carefully, because it determines your first year deduction.
How do I split land from building for depreciation?
Use county assessment records first. Most counties publish a land value and an improvement value, which you can use as a starting point. If those do not feel accurate, hire an appraiser to split the purchase price. Land is typically 15 to 25 percent of total value, but it varies. Once you have the split, keep it documented in your records, because you will need it if you are audited.
I never claimed depreciation on my rental. What do I do now?
File IRS Form 3115, which is a request to change your accounting method and catch up missed depreciation. You can do this even years after the purchase, and it often does not require amending every prior year. Act quickly, because failing to claim depreciation actually hurts you later when you sell (you owe recapture tax on depreciation the IRS assumes you took).
Can depreciation create a loss even if my property cash flows positively?
Yes. Depreciation is a non-cash paper loss. You can collect $15,000 per year in rent, pay $8,000 in expenses, have $7,000 in cash flow, and still show a $5,000 tax loss if depreciation on the property is $12,000. This is the magic of real estate: positive cash flow, negative taxable income.
Can I do a cost segregation study on a property I bought years ago?
Yes. You can perform a cost segregation study on older properties using Form 3115 to catch up the reclassified depreciation. This is one of the best-kept secrets in real estate tax planning. If you have a five or ten year old rental that was never studied, it might be worth revisiting now.
Is a cost segregation study worth the cost for my property?
It depends on whether you can use the deductions now. If you are a REPS, an STR operator with material participation, or a high-income owner who can absorb losses immediately, a $2,000 to $4,000 study often pays for itself in the first year through tax savings. If you already have suspended passive losses, cost seg creates more losses you cannot use, so the study cost is harder to justify.
Work with a CPA Who Invests in Real Estate Too
Depreciation and cost segregation are not fire-and-forget strategies. They require proper setup, careful documentation, and integration with the rest of your tax and entity planning. A CPA who also invests in real estate understands how these pieces fit together and whether cost segregation makes sense for your specific situation.
At Malabute and Company CPAs, we specialize in working with real estate investors. We analyze your portfolio, run the cost-benefit numbers on cost segregation studies, and build a depreciation schedule that accounts for every property, every purchase date, and every placed-in-service date. We also tie depreciation planning to your REPS status, entity structure, and passive loss strategy so every deduction counts.
If you have questions about whether depreciation or cost seg makes sense for you, join our free Facebook community, REI Tax Hack, where real estate investors share strategies and ask questions. Or if you are ready to build a comprehensive tax plan, we would welcome the conversation.
Internal Links
Spoke Articles (Children of /depreciation-and-cost-segregation/)
- How Depreciation Works / /how-depreciation-works/
- Common Depreciation Mistakes / /common-depreciation-mistakes/
- What Is Cost Segregation / /what-is-cost-segregation/
- Bonus Depreciation and OBBBA / /bonus-depreciation-obbba/
- Cost Segregation on Old Properties / /cost-segregation-on-old-property/
- Is Cost Segregation Worth It / /is-cost-segregation-worth-it/
Sibling Pillar Links
- Real Estate Professional Status and the Short-Term Rental Loophole / /real-estate-professional-status/
- Entity Structure (LLC, S-Corp, C-Corp) / /entity-structure-llc-s-corp-c-corp/
- Capital Gains, 1031, and Stepped-Up Basis / /capital-gains-1031-stepped-up-basis/
- Year-Round Tax Planning / /year-round-tax-planning/
- Bookkeeping and Working with a CPA / /bookkeeping-and-cpa/
- Rental Property Analysis and Wealth Building / /rental-property-analysis-wealth-building/
- Property Taxes, Extensions, and Tax Law / /property-taxes-extensions-tax-law/
If you want to talk through how this applies to your properties, book a discovery call.