Street Economics

Martin County, Florida

HJR 1 Homestead-Exemption Tax-Base Exposure

Martin County . 2025 final assessment roll

Snapshot

The Martin County read

Martin County fits the Bedroom Residential Monoculture archetype. The base is owner-occupied single-family housing at moderate value with thin commercial, industrial, or rental property — this is the maximum-exposure profile, because almost every dollar of value is the exact kind of property the amendment exempts. Strip the homesteads and little taxable base remains. At full $250,000 phase-in in 2028, 20.4% of the county’s non-school taxable base is exposed; the 2027 step at $150,000 puts that figure at 11.8%. High homestead share plus low commercial share means the exemption lands on nearly the whole base at once.

Of 79,037 residential housing units, 61.4% are owner-occupied, 13.7% are owned by out-of-state owners, and 24.9% are non-homestead but Florida-owned. The out-of-state ownership share at 13.7% does not trigger the high out-of-state callout threshold, and the larger non-homestead story here is the 24.9% Florida-owned non-homestead share — local landlords and in-state second-home owners who represent a meaningful slice of the residential base that the amendment does not exempt.

Land-use composition

Share of taxable value by category, Martin County, 2025 roll:

Residential property accounts for nearly three-quarters of the county’s just value, which is the structural condition that drives the exposure figure. Commercial, industrial, and multifamily together represent only about 10.1% of the base — a thin non-homestead spine relative to the residential mass sitting above it.

What the exposure band means

Exposure band: Moderate exposure. A meaningful but absorbable hit. The place has some non-homestead base to lean on. Mitigation is about steering future growth, not emergency response.

Looking ahead

Neither of the following changes the exposure figure calculated above.

First, beginning January 1, 2027, the annual assessment-increase cap on non-homestead property drops from 10% to 5%, covering commercial, industrial, and small residential rentals of nine units or fewer. Because capped values can only rise 5% per year, the main engine of base growth in these categories becomes transactions — a sale or change of control resets assessed value to market — so transaction velocity matters more to non-homestead base growth than it did under the old cap.

Second, new Florida residents who did not maintain a Florida permanent residence as of December 31, 2026 phase into the larger exemption over five years rather than receiving it all at once. This residency ramp cannot be read from the assessment roll, so all exposure figures here assume full application of the exemption. Near-term exposure could run slightly lower than modeled in areas where a meaningful share of recent homesteaders are still inside their five-year window.

Where the opportunity is

These mitigation opportunities are based solely on a read of the tax roll’s land-use composition. They do not account for whether local land development regulations and zoning permit the use, whether there is local obstruction, or the political dynamics that typically decide what actually gets approved. This is a starting point for a conversation, not a development plan.

• With commercial at only 5.5% of the county’s just value, the single highest-leverage move is building a commercial and employment spine. Converting a share of future growth from rooftops to taxable commercial square footage — a neighborhood-serving retail node, a small office or medical-office cluster, or a light-flex business park on an arterial — adds non-homestead value that the amendment does not touch. This is the move that changes the structural composition of the base over time.
• Multifamily rental is the second major lever. Apartments pay full freight under the amendment. At only 2.3% of just value, the rental base is thin. Allowing well-sited rental near jobs and transit adds non-homestead value and workforce housing simultaneously, and the 24.9% Florida-owned non-homestead residential share signals that local investor appetite for rental product already exists in the market.
• Concentration matters as much as volume. Rather than scattering commercial and rental growth across the county, directing new square footage and well-sited rental to an existing arterial or corridor builds a real non-homestead spine in one place instead of keeping it thin everywhere. A corridor strategy also makes future investment more legible to the market.
• The Other/Vacant category at 6.3% of just value represents land that has not yet been committed to a use. Future decisions about how that land is zoned and developed will either deepen the non-homestead base or extend the monoculture. Prioritizing commercial and industrial parcels for future growth rather than more subdivisions is the structural choice that determines which direction the base moves.
• Any existing employment anchor — a hospital, a college, a distribution facility, a government office complex — is already a non-homestead taxpayer in place. Protecting and intensifying those anchors is the lowest-cost mitigation move available, because the base is already there.

Watch-out: do not solve a revenue hole by approving more single-family subdivisions. Each new subdivision adds homestead value the amendment will exempt while adding service demand the millage must cover. That is the trap that created the exposure in the first place, and more of the same deepens it.

Source and scope

All figures are drawn from the Florida Department of Revenue 2025 final assessment roll, the most recent certified roll in the state’s possession. The roll is used here as a structural proxy for tax-base composition — it is not a dollar forecast for any specific budget year. HJR 1 / CS-HJR 1F is on the November 2026 ballot; the 2026 roll is the assessment roll in place when voters decide. If the amendment passes, the first roll actually affected is the 2027 roll (the $150,000 step), followed by the 2028 roll at full $250,000 phase-in. When the 2026 and later rolls are certified, the analysis re-runs on the new data.

Ownership shares are measured on a residential-unit basis. The out-of-state ownership figure is a mailing-address proxy: it counts residential units whose owner’s mailing-address state in the roll is a non-Florida state or country. It undercounts true outside ownership — an out-of-state owner using an in-state LLC mailing address counts as Florida — and it does not prove where an owner actually lives. It is the cleanest available stand-in for second-home and out-of-state investor ownership of housing, not a definitive residency determination.

This read is a land-use-composition starting point. It is not a comprehensive fiscal, economic, or legal analysis, and it is not a substitute for a full planning or financial review.

Place: Martin