The Fear That Stops Most Orlando Homeowners
We hear this concern on almost every ADU consultation: "I don't want to lose my Homestead Exemption." It is the single most common reason Orlando homeowners hesitate before building — and it is based on a misunderstanding of how Florida property tax law actually works.
This guide cuts through the confusion. The short version: your Homestead Exemption and your Save Our Homes cap are safe. The slightly longer version involves understanding exactly how the Property Appraiser assesses ADUs — and one specific scenario where the tax picture gets more interesting.
Common Myths vs. The Actual Law
Myth
"Adding a rental unit on my property means I lose my Homestead Exemption entirely."
Fact
Florida law protects the homestead exemption as long as you continue to use the primary residence as your permanent home. Renting a secondary structure on the same parcel does not remove homestead status.
Myth
"The whole property will be reassessed at market value once I add an ADU."
Fact
Only the ADU addition is assessed at current market value. The existing home's assessed value stays under the 3% Save Our Homes annual cap — exactly as it was before construction.
Myth
"I have to move out of my house to build an ADU under SB 48."
Fact
SB 48 explicitly removed the owner-occupancy requirement. You can build and rent an ADU while living in the main house full time, preserving your Homestead Exemption throughout.
Myth
"Renting the ADU on Airbnb will trigger a homestead exemption audit."
Fact
Short-term rental of a portion of a homesteaded property is allowed without automatic loss of exemption, provided your primary domicile remains unchanged. However, if the ADU is a separate parcel, rules differ — discuss with your Property Appraiser's office.
How the Property Appraiser Actually Handles ADU Additions
When you pull a permit and complete an ADU, the Orange County Property Appraiser receives a notice from the Building Division after your Certificate of Occupancy is issued. The appraiser then performs what is called a "Supplemental Assessment" — a mid-year reassessment of the just-completed improvement.
Here is the critical point: the supplemental assessment applies only to the ADU addition. It does not trigger a reset of your primary residence's assessed value. Your existing Save Our Homes cap continues to compound forward at the 3% maximum annual increase — unchanged by the ADU construction.
The Tax Math: What Actually Changes After an ADU Build
| Item | Before ADU | After ADU |
|---|---|---|
| Primary Home Assessed Value | $260,000 (capped) | $260,000 (unchanged) |
| Save Our Homes Cap | Active — 3% max/yr | Active — still applies to main home |
| Homestead Exemption | $50,000 deduction | $50,000 deduction — still applies |
| ADU Assessed Value | N/A | ~$75,000–$90,000 at current market rate |
| ADU Annual Tax (at ~1.2% effective rate) | N/A | ~$900–$1,080/yr |
| ADU Gross Rent Income | N/A | $1,400–$1,900/month |
| Net Position | — | +$15,720–$21,720/yr income vs. $900–$1,080/yr new tax |
The new property tax from the ADU addition is real — but it is a fraction of the rental income it generates. In every scenario we have modeled for Orlando properties, the ADU produces a positive net cash position even after the additional annual tax.
The "Granny Flat" Assessment Reduction: The Hidden Tax Benefit
Under Florida Statute §193.703, a homeowner may apply for an "Homestead Property Assessment Reduction for Living Quarters of Parents or Grandparents." This applies when you construct or retrofit a portion of your homesteaded property to house a parent or grandparent aged 62 or older.
If approved, the Property Appraiser assesses the improvement (your ADU) at the lesser of:
- The actual construction cost, or
- The current just value of the improvement
In practice, this means your $90,000 garage conversion built for an elderly parent may be assessed at construction cost rather than the $110,000–$130,000 it might add to the property's market value. This can reduce annual taxes on the ADU portion by $200–$450/year.
To qualify, the parent or grandparent must use the space as their primary place of residence. The homeowner must file annually with the Property Appraiser's office, and the application must be submitted by March 1st of the tax year.
What Happens to Homestead Status If You Eventually Move Out?
If you ever move out of the primary residence and the property becomes entirely renter-occupied, you must relinquish the Homestead Exemption by filing with the Property Appraiser's office. At that point, the entire property — main house and ADU — would be reassessed at current market value. This is true regardless of whether an ADU exists, and is a function of Florida's homestead rules, not the ADU itself.
"The Granny Flat tax reduction (F.S. §193.703) is used by fewer than 5% of the homeowners who qualify for it — mostly because their contractor never told them it existed. We recommend every client building an ADU for an aging parent apply for it. The application is two pages, filed with the Orange County Property Appraiser by March 1st. In the builds we've managed, this has saved clients between $2,000 and $4,500 in cumulative taxes over the first decade. It doesn't sound large, but it's free money that most people walk past completely unaware."