Self-storage operators in Washington state woke up on April 1, 2026, facing a tax obligation that did not exist three months earlier. Under Engrossed Senate Substitute Bill 5794, signed into law in 2025, rental income from individual storage units at self-service storage facilities is now subject to Washington's Business and Occupation tax under the Service and Other Activities classification. The same income had been treated as real estate rental for decades, a category that was not subject to B&O tax. That changed with one legislative session.
The shift is not a rate increase on an existing obligation. It is a reclassification that removes a tax exemption the industry had operated under since Washington's B&O framework was established. The applicable B&O rate is 1.5% to 1.75% on gross revenue. The first quarterly payment is due July 25, 2026. Facilities that previously qualified for active non-reporting status because they had no taxable sales are no longer eligible if their annual income exceeds $125,000 — which includes nearly every commercial self-storage operation in the state.
Washington's move is not happening in isolation. Across Illinois, a string of municipalities have proposed or enacted 5% sales taxes on self-storage rentals over the past 18 months, with active debates still underway in several Chicago-area communities. The pattern in both states is the same: legislators and budget planners discovered that self-storage is a high-margin industry sitting outside the standard tax base, and they moved to change that.
What Washington's B&O Tax Actually Means for Operators
Washington's B&O tax is applied to gross revenue, not profit. There are no deductions for labor, materials, capital costs, or existing property taxes before the B&O liability is calculated. A facility generating $800,000 in annual rental income pays B&O tax on the full $800,000, not on the margin after expenses.
The practical implication is that the new tax hits operators at a moment when self-storage is already navigating rate compression. Street rates in Washington markets have followed the national trend of declining year-over-year. Layering a 1.5% gross revenue tax on top of that compression means operators face reduced per-unit revenue from pricing pressure and new tax cost simultaneously, with no mechanism to offset the tax against reduced revenue from rate softness.
The Washington Self Storage Association has stated publicly that it believes ESSB 5794 raises constitutional concerns under the uniformity clause of the Washington Constitution. The core argument is that the law selectively taxes rental income from self-service storage facilities while leaving rental income from office buildings, industrial properties, retail space, and multifamily housing exempt. WSSA's position is that taxing only a subcategory of real estate rental income, while exempting substantively similar income from other property types, constitutes discriminatory treatment under state constitutional standards. The association has indicated that litigation is likely, though as of May 2026 no formal challenge has been filed.
Illinois: A Municipal Patchwork That Keeps Growing
Illinois has produced the most active municipal-level self-storage tax activity in the country over the past 18 months. The pattern began with smaller Chicago-area municipalities testing a 5% sales tax on self-storage rentals as a budget tool and has spread across communities where the industry had previously operated with no rental-specific tax.
Rolling Meadows included a 5% self-storage municipal rental tax in its 2026 budget, one of several municipalities to formally adopt or advance the idea. Crystal Lake tabled a similar proposal after receiving opposition from local facility owners and state-level industry association advocacy. Mundelein's Village Board rejected a 5% tax outright after the Illinois Self Storage Association and the national Self Storage Association mounted coordinated opposition, including tenant-impact arguments.
Lake in the Hills and Plainfield have also raised the idea in budget discussions. Rockford took a different approach, restricting self-storage development to industrial zones rather than imposing a rental tax, effectively limiting new supply through land use rather than taxing existing revenue.
The common thread in communities that have pulled back from these proposals is organized opposition from the Self Storage Association network. The SSA and its state affiliates have argued consistently that self-storage rental taxes function as pass-through costs: operators adjust pricing to offset the tax, and the effective burden falls on tenants, including a disproportionate share of lower-income households using storage to compensate for housing that does not meet their space needs.
How Operators Are Responding
The most immediate operational response in Washington is lease and pricing adjustments. Operators are reviewing rental agreement language to determine whether existing contracts permit mid-term rate increases to offset B&O tax cost, and whether new leases should include explicit acknowledgment of tax obligations. Law firm Stoel Rives, which has published guidance on the Washington change, notes that operators need to assess their registration and filing obligations with the Washington Department of Revenue before the July 25 payment deadline.
On pricing, some Washington operators have moved to absorb the B&O cost through modest rate increases rather than explicit pass-through, which preserves simpler billing and avoids the customer friction that a separate line-item tax fee would generate. Others are modeling whether to disclose the tax component separately in pricing materials, a practice that creates transparency but also highlights the cost increase explicitly.
In Illinois municipalities where 5% taxes have passed or are advancing, the math is more direct. A facility generating $500,000 in annual rental revenue faces a $25,000 annual tax obligation at 5%, roughly equivalent to the NOI impact of keeping one or two 10x10 units vacant for the year. At a multi-facility portfolio, the cumulative impact of municipal taxes across different jurisdictions produces the kind of compliance complexity that independent operators, who do not have dedicated legal and accounting staff, absorb disproportionately.
The Broader Pattern: Self-Storage as a Budget Target
The self-storage industry's tax vulnerability stems from a combination of factors that legislators and budget staff have identified across multiple states and municipalities: high occupancy rates in most markets, strong cash flow margins relative to many other commercial property types, a tenant base that generally does not organize politically, and decades of operating under tax treatments that predate the modern industry's scale.
State legislators who drafted Washington's ESSB 5794 projected the B&O tax would generate $16.2 million in state revenue in 2026 alone. Extrapolated to 2035, the projection reaches $489 million. Those are meaningful figures for a state managing a significant budget shortfall, and they are the same dynamics that drive municipal councils toward a 5% self-storage rental tax when seeking new revenue without broad-base tax increases.
The SSA's track record in defeating municipal proposals, including Mundelein, is relevant. But defeating individual proposals through advocacy is a different challenge than overturning a state-enacted law. The constitutional argument WSSA is preparing would require a court ruling, not a council vote, and the timeline for that challenge is measured in years rather than months.
The Numbers Worth Writing Down
- Washington ESSB 5794 effective date: April 1, 2026; first payment due July 25, 2026
- Washington B&O tax rate on self-storage gross revenue: 1.5 to 1.75%
- B&O tax applies to gross revenue with no deductions for labor, costs, or existing property taxes
- Facilities with >$125,000 annual income lose active non-reporting status
- Washington projected B&O revenue from self-storage: $16.2 million in 2026; $489 million through 2035
- Washington Self Storage Association: constitutional challenge likely (uniformity clause argument)
- Illinois municipalities with active or recent 5% self-storage rental tax proposals: Rolling Meadows, Crystal Lake, Mundelein, Lake in the Hills, Plainfield
- Mundelein: proposal rejected after ISSA and SSA opposition
- Rolling Meadows: 5% tax included in 2026 budget
The Advocacy Window Is Narrowing
Washington's tax is law. The constitutional challenge, if it moves forward, will take time. Illinois municipal proposals remain contested, with the SSA and state affiliates continuing to oppose new proposals case by case. Neither situation is resolved, and both are active in a market year when operators are already absorbing rate pressure from a demand environment they do not control.
The industry's consistent advocacy message — that taxes on self-storage rentals function as a tax on tenants, not on operators — has worked at the municipal level in several communities. It did not work at the state level in Washington, and the projected revenue figures suggest that other states facing budget pressure will run the same calculus. Self-storage's position as a high-cash-flow, low-political-organized-tenant-base industry makes it a recurring target that operators and associations will need to continue fighting state by state, municipality by municipality, for the foreseeable future.
Sources
- Self-Storage Businesses Now Subject to B&O Tax, Washington Department of Revenue
- Self-Storage Facilities Face New B&O Tax Obligations in Washington, Stoel Rives LLP
- Washington DOR Announces B&O Tax on Self-Service Storage Rentals Starting April 2026, Bloomberg Tax
- Washington Considers Self-Storage Tax to Resolve Budget Shortfall, Inside Self-Storage
- WA Storage Unit Tax Could Raise Nearly $500M by 2035 — If It Holds Up in Court, The Center Square
- Washington Taxes Self-Storage Rentals as a Service Starting April 1, 2026, Sales Tax Institute
- Rolling Meadows, IL, Considers 5% Self-Storage Tax, Inside Self-Storage
- Mundelein, IL, Board Rejects Self-Storage Sales Tax After Opposition, Inside Self-Storage
- Are Washington Lawmakers About to Tax Storage Unit Rentals?, Washington State Standard
- 2025 Washington State Legislative Session Update: Prepare for Excise Tax Changes, Moss Adams