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

Alaska has not taxed individual income since 1980, when surging Prudhoe Bay oil revenue let the legislature repeal it, and it has never reinstated one. That means individuals, sole proprietors, and LLCs or partnerships owned entirely by natural persons can hold rental real estate without ever filing an Alaska income tax return. In states that decouple from federal bonus depreciation, an investor has to add back part of a large first-year deduction on their state return and recover it slowly over later years. For these owners, that mechanism simply does not exist, so a cost segregation study's accelerated first-year deduction flows through to federal taxable income with nothing to reconcile at the state level. The one nuance: an Alaska S-corporation must still file Form 6000 (page 1) with the Department of Revenue, and a partnership or LLC with any corporate or partnership-level partner must file Form 6900 — neither filing produces Alaska tax due, but the entity-level paperwork obligation is real even when no add-back results.

Alaska is not entirely without a corporate income tax: the Alaska Net Income Tax Act (AS 43.20) imposes a graduated corporate rate of 0% to 9.4% on C-corporations. For any Alaska entity return that is filed — C-corporation, S-corporation, or a partnership required to file Form 6900 — the state adopts the Internal Revenue Code by reference under AS 43.20.021, which is the actual mechanism that lets 100% federal bonus depreciation flow through without a state add-back. Separately, under AS 43.20.144, the state freezes oil and gas producers to the depreciation rules under Internal Revenue Code Section 167 as it existed on June 30, 1981, as carried out through the implementing regulation at 15 AAC 20.480 — a narrow, industry-specific decoupling that predates modern bonus depreciation entirely. Almost no short-term or long-term rental owner is affected by it; it matters mainly for oil and gas corporations, not for an LLC that owns a cabin or a fourplex.

Property taxes are the other half of the Alaska equation, and they are entirely local. There is no statewide property tax; boroughs and municipalities set their own mill rates, and published estimates of the average effective rate across the state generally run from roughly 0.8% to 1.1% of assessed value depending on the source, methodology, and jurisdiction — with parts of the vast Unorganized Borough levying no property tax at all. Urban areas like Anchorage tend to run above the state average, while more rural boroughs run below it. None of that changes the depreciation math, but it does mean an Alaska investor's total carrying cost, and therefore the relative impact of any tax-timing strategy, varies significantly by where in the state a property sits.

Under default IRS rules, a residential rental building is depreciated on a straight-line basis over 27.5 years, and a commercial building over 39 years — the same schedule whether the property is a rustic Kenai River cabin or a downtown Anchorage office building. A cost segregation study is an engineering-based analysis that goes through the property component by component and identifies the portion of the purchase price attributable to items the IRS treats as separate, shorter-lived personal property or land improvements: cabinetry, flooring, specialty electrical and plumbing, decking, fencing, and paved or graded exterior work, among others. Those components can be depreciated over 5, 7, or 15 years instead of 27.5 or 39.

The payoff comes from bonus depreciation. The One Big Beautiful Bill Act (OBBBA), signed into law in July 2025, permanently restored 100% first-year bonus depreciation for qualifying property acquired after January 19, 2025. Any component a study reclassifies into a 5-, 7-, or 15-year life is generally eligible to be fully expensed in the year the property is placed in service, rather than depreciated a few percent at a time over decades. That shift — from a slow trickle of deductions to a large deduction concentrated in year one — is the entire mechanical reason cost segregation exists as a strategy.

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 $650,000 short-term rental cabin near Seward, along the Kenai Fjords cruise route, and places it in service in 2026. After allocating roughly 20% of the purchase price to the underlying land — $130,000 — the depreciable building basis is $520,000. On a standard straight-line residential schedule, that would produce about $18,900 of depreciation in the first full year. An engineering-based cost segregation study might instead find that a meaningful share of that basis — decking, dock structures, specialty electrical for hot tubs, gravel and landscaping, interior finishes — qualifies for 5-, 7-, or 15-year treatment. If that reclassified amount comes to roughly $150,000, the OBBBA's 100% bonus depreciation rule would allow the owner to deduct that entire $150,000 in year one, on top of the remaining building depreciation. For an individual owner or a pass-through entity with no Alaska filing obligation, none of that deduction is added back at the state level — the full federal benefit is what the owner actually realizes. These are simplified, round numbers for illustration, not a forecast of what any specific property would produce.

Cost segregation is not limited to the year a property is purchased. If you have owned an Alaska rental for several years without ever having a study done, a look-back study lets you claim the missed depreciation without amending a single prior-year tax return. The mechanism is IRS Form 3115, Application for Change in Accounting Method, paired with a Section 481(a) adjustment. That adjustment sums up the difference between the depreciation you actually claimed and the depreciation you should have claimed under a properly segregated schedule, and lets you take that entire catch-up amount as a deduction in the current tax year. For an owner of a cabin near Talkeetna or a rental duplex in Fairbanks that has been generating rental income for years on a plain 27.5-year schedule, that catch-up can be substantial — and for an owner with no Alaska filing obligation, the entire benefit again flows through at the federal level with no state add-back to track.

• Short-term rental and Airbnb hosts in Alaska's active vacation-rental markets — Anchorage, Seward, Talkeetna (the gateway to Denali National Park), Kenai, Homer, Girdwood, and Fairbanks — where seasonal tourism, fishing, and aurora and glacier travel support strong nightly rates
• Long-term rental owners with residential or multifamily property in Anchorage, Fairbanks, Juneau, or the Kenai Peninsula who want to accelerate depreciation on an existing hold
• Recent buyers or renovators who purchased or substantially improved an Alaska property in 2025 or 2026 and can capture 100% bonus depreciation on the qualifying components
• High-income owners exploring the short-term rental material participation strategy, which lets active participants in a qualifying short-term rental (average guest stay of 7 days or fewer, combined with material participation) use rental losses to offset other active income, including W-2 wages
• Owners weighing a sale or refinance who want an accurate, defensible allocation of building components before a transaction changes their basis picture