What your Save Our Homes benefit is worth on the next house

How the two formulas differ

Buying up. If the new home's just value is greater than or equal to the old one's, s. 193.155 gives you the whole benefit: the new assessed value is the new just value minus the lesser of $500,000 or the gap between just and assessed on the old homestead. The benefit transfers intact.

Buying down. If the new home's just value is lower, the benefit is proportional rather than whole. The new assessed value is the new just value divided by the old just value, multiplied by the old assessed value. You keep the same ratio of discount, not the same dollar amount — which is the part most people get wrong, because the headline figure they have been told is the dollar gap on the old house.

Either way, if the resulting gap between just and assessed on the new homestead would exceed $500,000, the assessed value is raised until the gap is exactly $500,000. That is the cap, and it is on the transferred benefit, not on the value of the house.

What this calculator does and does not do

It derives the tax rate from your own current bill rather than from a millage table. Your bill divided by your current taxable value gives the effective rate on your parcel, including whichever school, county, municipal and special district levies actually apply to you. A published millage table goes stale and does not know which districts you are in. The limit of that method is that it assumes the new home sits under a similar total millage, which is a fair assumption within south Miami-Dade and a poor one if you are moving between taxing authorities. If you are, treat the tax figure as indicative and ask the appraiser's office.

The new assessed value is not the purchase price. Sections 193.011(1) and (8) require the appraiser to consider net proceeds after the usual costs of sale, and a deduction of roughly 15 percent is commonly applied. It is discretionary rather than automatic, which is why it is an input you can change. Set it to zero to see the worst case.

The exemption handling matches the other calculators on this site: $25,000 against all levies, then a second band that only bites on assessed value above $50,000 and does not apply to school levies. The second band is inflation-adjusted each year under s. 196.031.

Three things that decide whether you get it at all

The three-year window. Section 193.155 requires that you held a homestead exemption as of 1 January in one of the three years immediately before establishing the new one. Abandon the old homestead and wait too long and the benefit is gone, not reduced.

You have to apply. Portability is not automatic and does not follow you because the county can see both parcels. It is a separate form filed with the new homestead application, and the deadline is the same 1 March. Missing it is the most common way people lose a benefit they were entitled to.

Two owners combining. If two people who each had their own homestead buy one house together, the reduction is limited to the higher of the two benefits, not the sum. The statute is explicit about that.

Which of these applies to your situation, and what the appraiser will actually accept, is a question for the Property Appraiser's office or a Florida tax professional. This page is arithmetic, not advice.

Why this decides an upmarket move

The reason this matters more here than the raw numbers suggest: a long-held homestead in Homestead, Florida City or Cutler Bay can carry a very large gap between just and assessed value, because Save Our Homes has been suppressing the assessment for years while the market moved. That gap is often the thing that makes a move up into the Kendall corridor or Palmetto Bay affordable, and it is invisible on every listing portal, which shows you the seller's tax bill rather than yours. Work it out before you decide the next house is out of reach.

The companion page, what the tax will actually be, handles the other half of this: what a buyer pays when there is no benefit to carry across. If you are selling the current house as part of this, the net sheet works out what you walk away with.