How to Use Depreciation & Cost Segregation to Save Big on Your Real Estate Taxes

You own a rental property that makes money every month. What if we told you it could also show a loss on your tax return — and that loss could reduce what you owe on your other income? That's the power of depreciation and cost segregation. Here's how it works and what you need to know before using it.

What Is a Cost Segregation Study?

When you buy a rental or commercial building, the IRS makes you depreciate it over 27.5 years (residential rental) or 39 years (commercial). That's a small deduction spread over decades.

A cost segregation study speeds that up. It identifies the parts of your property that aren't permanently structural — flooring, cabinetry, appliances, landscaping, parking lots, certain electrical and plumbing components — and reclassifies them into shorter depreciation schedules of 5, 7, or 15 years. Better yet, with bonus depreciation now available at favorable rates in 2025 (more on that below), many of those components can be written off entirely in Year 1 instead of over 5, 7, or 15 years.

Example: You buy a rental property for $1 million. A cost seg study identifies $250,000 of non-structural components. Without cost seg, you'd deduct roughly $9,000/year on that $250,000 over 27.5 years. With cost seg and bonus depreciation, you can potentially deduct the full $250,000 in the year you bought it.

Your Rental Can Make Money and Still Show a Loss

This is the part most people miss. Your rental can produce positive cash flow every month and still show a paper loss on your tax return after depreciation. That loss can offset your other income — but how much depends on your situation.

If your modified AGI is under $100,000 and you actively participate in managing the rental (approving tenants, setting rents, making decisions — you don't have to do it personally, but you need to be genuinely involved), you can deduct up to $25,000 of rental losses against your ordinary income. This benefit phases out gradually between $100,000 and $150,000 of modified AGI and disappears entirely above $150,000.

If you qualify as a real estate professional, the income limits go away entirely. But this isn't just a label — the IRS has a specific definition. You must spend more than 750 hours per year in real property trades or businesses, and that must represent more than 50% of your total working hours. Meeting those tests alone isn't enough, though. You still have to materially participate in each rental property. If you own multiple rentals, you can elect to group them as a single activity — which is often the move that actually makes the strategy work. If you're married, only one spouse needs to qualify, but they must meet the tests on their own; you can't combine hours.

If you own a short-term rental (Airbnb/VRBO) where the average guest stays 7 days or less, your rental isn't treated as a passive activity at all — which means the income limits don't apply. You still have to meet a material participation test, though. The most common one used here is participating more than 100 hours and more than anyone else involved in the property. There are other ways to qualify too (500+ hours total is the cleanest), but 100 hours alone doesn't get you there — you need to clear both parts of the test.

One thing to flag on short-term rentals: when you escape the passive loss rules by treating the rental as a business, that can also mean the net income becomes subject to self-employment tax — an additional 15.3% on earnings up to the Social Security wage base. That's a real cost that needs to be factored into the analysis.

If any of these strategies seem applicable to your situation, please reach out to us so we can sort through the details with you.