Cost Segregation Study in Mississippi for Airbnb and Short-Term Rental Investors

For years, Mississippi taxpayers who claimed federal bonus depreciation under IRC Section 168(k) had to add that deduction back on their state return and instead depreciate the asset using slower, pre-bonus MACRS schedules — a textbook decoupled state. That changed with House Bill 1733, signed into law in 2023, which amended Miss. Code Ann. Section 27-7-17. Rather than simply adopting whatever bonus percentage Congress sets for a given year, the statute gives taxpayers a choice for qualified property and qualified improvement property placed in service in tax years beginning after December 31, 2022: elect a fixed 100% state depreciation allowance, or depreciate the property under 26 U.S.C. Section 168 as if no election were made. The election must be made on the original return by its due date, including extensions, and once made it is generally irrevocable unless the Commissioner of Revenue consents to a change. It was a deliberate break from the federal phase-down schedule in effect at the time (80% bonus in 2023, 60% in 2024), but it only helps taxpayers who actually make the election.

The practical effect for 2026 investors: because the One Big Beautiful Bill Act (OBBBA) separately restored 100% bonus depreciation at the federal level for qualifying property acquired after January 19, 2025, Mississippi's elective 100% allowance and the current federal 100% allowance now point the same direction for taxpayers who elect in. A cost segregation study that reclassifies components of a Mississippi rental property into 5-, 7-, and 15-year buckets can generally be written off at 100% on both the federal and Mississippi returns in the placed-in-service year, without the addback-and-recompute step decoupled states such as California require — but only if the Section 27-7-17 election is timely made. Miss the deadline, and the Mississippi return defaults to regular IRC Section 168 depreciation while the federal return still gets full bonus. Investors should confirm the election is filed correctly with a CPA, since the Mississippi Department of Revenue periodically issues guidance interpreting how this statute interacts with future federal changes.

Property taxes add another favorable layer, though the specific numbers depend on how the property is used. Per the Tax Foundation, Mississippi's average effective property tax rate is 0.58% of home value, one of the lowest in the country. That statewide average is driven largely by owner-occupied Class I property, which is assessed at just 10% of true value and can carry a homestead exemption on top. A non-owner-occupied short-term or long-term rental — the kind of property this page is about, whether a Gulf Coast condo, an Oxford rental house, or Delta or Piney Woods acreage held for investment — instead falls into Class II, assessed at 15% of true value with no homestead exemption, since that exemption is limited to an owner's primary residence. Even at the higher Class II ratio, Mississippi's overall property tax burden remains modest by national standards, so the cash a cost segregation study frees up generally isn't eaten up the way it might be in a high-millage state — but investors should plan around the Class II rate for a rental, not the owner-occupied rate.

When you buy a rental property, the IRS default is to spread its cost over a long, straight line: 27.5 years for a residential rental, 39 years for a commercial building. A cost segregation study is an engineering-based analysis that walks through the property — site work, flooring, cabinetry, decking, appliances, parking areas, landscaping, and specialty electrical or plumbing — and identifies which components legally qualify for much shorter IRS recovery periods, typically 5, 7, or 15 years instead of 27.5 or 39.

Those reclassified components are exactly the kind of property that qualifies for bonus depreciation. Under the One Big Beautiful Bill Act, signed into law in July 2025, 100% bonus depreciation was permanently restored for qualifying property acquired after January 19, 2025, meaning an investor can potentially deduct the full cost of the reclassified 5-, 7-, and 15-year components in the year the property is placed in service rather than over decades. On a typical rental property, a study often reclassifies somewhere in the range of 20% to 35% of the depreciable basis, though the exact share always depends on the specific property and its components.

For illustration only — your results depend on your property and tax situation, and this is not a projection of actual savings.

Suppose an investor buys a short-term rental condo near the beach in Biloxi for $450,000, with $360,000 allocated to the depreciable building after backing out land value. Under standard 27.5-year straight-line depreciation, that produces roughly $13,000 of depreciation in year one. A cost segregation study might reclassify around 25% to 30% of that basis — call it $95,000 — into 5-, 7-, and 15-year property. Under 100% bonus depreciation, that $95,000 could potentially be deducted in year one on top of the remaining building's regular depreciation, producing a first-year deduction well above what straight-line depreciation alone would generate. For an investor who also qualifies for the short-term rental material participation strategy discussed below, that deduction could offset active income in the same year. Actual figures depend on the property's specific components, basis allocation, and the investor's individual tax position — a licensed cost segregation provider and CPA should model your real numbers.

Many Mississippi investors don't hear about cost segregation until well after closing on a property — sometimes years later. That's not a dead end. If you've owned a rental for a year or more without running a study, a look-back cost segregation study lets you claim the depreciation you missed without amending any prior tax returns. The mechanism is IRS Form 3115, Application for Change in Accounting Method, paired with a Section 481(a) adjustment that lets you catch up the entire missed depreciation as a single deduction on the current year's return, whether the property was purchased two years ago or ten. Because Mississippi's own elective 100% state-law depreciation allowance has been available for qualified property placed in service since the start of 2023, owners who bought Mississippi rental property any time in the past few years may find a look-back study particularly worthwhile — just note that a look-back study affects the federal return through Form 3115, while the Mississippi election for the placed-in-service year is a separate, time-sensitive filing step your CPA needs to check.

• Short-term rental and Airbnb hosts operating on the Mississippi Gulf Coast in Gulfport, Biloxi, or Ocean Springs, where beach and casino tourism support strong nightly demand
• Owners of Airbnb or Vrbo properties in Oxford, where University of Mississippi football weekends and the Double Decker Arts Festival help drive some of the highest nightly rates in the state
• Investors with historic-district or riverside rentals in Natchez or Vicksburg catering to heritage and Mississippi River tourism
• Long-term single-family and small multifamily rental owners across the Jackson metro, the Gulf Coast, and college towns such as Oxford and Starkville
• Investors who recently purchased, built, or substantially renovated a rental property and haven't yet had a study performed
• High-income W-2 earners or business owners exploring the short-term rental material participation strategy, which requires an average guest stay of seven days or less plus material participation in operating the property, to apply rental losses against active income