Calculators
Miami-Dade Homestead Portability Calculator
This calculator is for Miami-Dade homeowners with a homestead in place who are weighing a move. It estimates how much of your Save Our Homes benefit transfers to the next house and what that saves you in the first year, using the 2026-27 adopted millage and the homestead exemption Amendment 3 sets for the year you move in: $150,000 off non-school taxes in 2027 and $250,000 from 2028. Illustrative estimate on those assumptions; it is not a quote of a tax bill.
Run Your Own Portability Math
Enter the just/market value and assessed value from your TRIM notice, plus the price of the home you are considering. The calculator estimates your portability transfer, your annual tax with and without portability, and an illustrative ten-year total, using the adopted combined millage for the area you pick and the Amendment 3 exemption for the first tax year you pick. The ten-year figure holds values and rates flat: the first year under its own exemption, then nine years under the 2028 rule. It does not forecast future tax rates, assessments or your continued eligibility.
From your TRIM notice or miamidadepa.gov. This is the appraiser's value, not your estimated sale price.
Also from your TRIM notice or miamidadepa.gov
For a new purchase, the appraiser usually sets the first fully reassessed just/market value below the sale price; 85% of it is a planning assumption, so adjust it if you have a better read
2026-27 adopted combined millage. Full breakdown in the millage guide.
Pick 2027 if the new home is homesteaded by January 1, 2027. Amendment 3 takes up to $150,000 off non-school taxes in 2027 and up to $250,000 from 2028. Portability itself does not change.
Estimates based on the 2026-27 adopted combined millage for the area you select and the Amendment 3 homestead exemption: $25,000 off school taxes, and up to $150,000 in 2027 or $250,000 from 2028 off everything else. Rates are reset every September and non-ad valorem assessments are not included. The $500,000 portability cap applies. Always verify with the Miami-Dade Property Appraiser before relying on these numbers for a transaction.
Rates last verified October 2026 against the 2026-27 millage adopted at the September 2026 final budget hearings.
How this works
The calculator reads the difference between your current home's just/market value and its assessed value as your Save Our Homes benefit. If the new home's value is equal or higher, the whole benefit transfers, up to the $500,000 cap. If you are downsizing, the benefit transfers in proportion to the new home's value, and the portion that does not transfer is permanently lost.
From there it figures the new assessed value and taxes it in two pieces, the way the county does. School levies get the $25,000 homestead exemption. Every other levy gets the Amendment 3 exemption for the first tax year you pick: up to $150,000 in 2027 and up to $250,000 from 2028. Portability itself is unchanged, including the $500,000 cap, but on a low ported assessment the larger exemption already covers part of what the benefit would have saved, so the saving can come out smaller than under the 2026 rules. Each piece is multiplied by its share of the 2026-27 millage for the area you select. The result is your estimated annual tax with and without portability, the yearly savings between them, and what that difference adds up to over ten years.
The tool is free and runs entirely in your browser, so the values off your TRIM notice never leave the page. The pillar guide below walks through the same math by hand, including the three-tax-year window you have to claim portability after a move.
