The Thing You Are Porting
Once a Florida home has a homestead exemption, its assessed value can rise no more than 3% a year, or the change in the consumer price index if that is lower. Market value is not capped. Hold the home through a decade of appreciation and the two numbers drift a long way apart.
That gap is the Save Our Homes benefit, and it has a precise definition:
Benefit = just (market) value − assessed value
A home the appraiser values at $600,000 but assesses at $392,000 carries a benefit of $208,000. That is $208,000 of value you are not being taxed on. Sell the house and, absent portability, it vanishes: the buyer's assessment resets to full market value, and you start again from scratch at your new place.
Portability is the rule that stops that happening. You can transfer up to $500,000 of accumulated benefit to your next Florida homestead.
Buying Up vs Buying Down
This is where most explanations go wrong. There are two different calculations, and which applies depends on the just value of the new home against the old one — not the price you paid, and not the assessed values.
Buying up (new just value is equal to or higher than the old)
You transfer the full benefit, capped at $500,000.
Worked example. Old home: just value $600,000, assessed $392,000, so a benefit of $208,000. New home: just value $750,000. You transfer the whole $208,000. The new assessed value starts at $750,000 − $208,000 = $542,000, and your homestead exemption then comes off that. Without portability you would have started at $750,000.
Buying down (new just value is lower than the old)
You transfer a proportional share, worked out as the ratio of the two just values:
Transferred benefit = (new just value ÷ old just value) × old benefit
Worked example. Same old home: just value $600,000, benefit $208,000. New home: just value $400,000. The ratio is 400,000 ÷ 600,000 = 0.667. You transfer 0.667 × $208,000 = $138,700. The new assessed value starts at $400,000 − $138,700 = $261,300.
The logic is that you keep the same percentage of protection, not the same dollar amount. Retirees downsizing are often startled by this: the smaller house can carry a proportionally smaller shield, and because you also lose any locally adopted long-term-residency exemption tied to the old address, the bill sometimes goes up even though the house got cheaper. Run the numbers before you list.
The Three-Year Window
You must establish the new homestead within three tax years of January 1 of the year you abandoned the old one. It is counted in tax years, not in 36 months, and that distinction decides real cases.
Work it through: you abandon the homestead during 2026 (you sell, or you stop using it as your permanent residence). January 1, 2026 starts the clock. You must have a new Florida homestead in place — owned and occupied as of January 1 — by the 2029 tax year. In calendar terms that can be anywhere from just over two years to nearly four, depending on where in 2026 you moved. Moving in December buys you far more usable time than moving in January.
The window was two years until Florida voters extended it to three in 2020, so older articles and even some county handouts still say two. It is three.
How to Claim It
- File the new homestead application (DR-501) with the property appraiser in the county of the new home, by March 1.
- File form DR-501T, "Transfer of Homestead Assessment Difference", at the same time. This is the portability form. Filing the homestead application alone does not give you portability — the transfer is not automatic, and nobody will chase you for it.
- Give the old parcel's details: county, address and parcel number. The two counties verify the benefit between themselves.
- Check the next TRIM notice in August to confirm the transferred amount actually appears. If it does not, or the figure is wrong, you have 25 days from the mailing date to petition the Value Adjustment Board.
Portability works between any two Florida counties — Miami-Dade to Escambia is fine. It does not work across state lines in either direction. And it applies only to the Save Our Homes assessment difference, not to any other exemption: those you re-apply for at the new address.
Two Owners, and Splitting the Benefit
Where two people jointly held the old homestead and now go separate ways, the benefit is divided. Each former owner can take up to their share of the accumulated benefit to a new homestead, and the total transferred cannot exceed what the original property had. Spouses who move to a new home together transfer the benefit jointly in the ordinary way.
If one spouse already had a homestead and the other is added to a new one, or if there is a divorce in the middle of a move, this gets fact-specific quickly and the county property appraiser's exemption office is the right place to take it — before you file, not after.
What Kills the Benefit
- Letting the three years lapse. The most common and the most expensive. Renting for a few years while you decide where to settle can quietly burn the whole window.
- Filing DR-501 but not DR-501T. You get the exemption, you silently lose six figures of assessment protection.
- Assuming the price you paid is the just value. The appraiser sets just value independently. A bargain purchase does not increase your transferred benefit, and overpaying does not reduce it.
- Moving out of Florida and back. The clock does not pause for an out-of-state detour.
- Missing March 1 at the new address, which pushes the whole thing a year later and can push it past the window.
Bottom Line
If you have held a Florida homestead through any period of appreciation, the accumulated Save Our Homes benefit is probably the largest single tax asset attached to your house, and it is portable up to $500,000. Buying up keeps all of it; buying down keeps a proportional share. File DR-501T with the new homestead application by March 1, and confirm the number on the TRIM notice that August.
New to the exemption entirely? Start with the Florida homestead exemption guide. Selling rather than moving within Florida, and worried about the gain? See capital gains tax when you sell your home.
General information, not legal or tax advice. Portability calculations depend on figures only your county property appraiser can confirm — check with them before making a move that depends on the result.