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Mello-Roos + special tax districts — the property-tax extras you didn't see
Property tax isn't just the county millage rate. Many newer subdivisions carry special-district taxes that add hundreds-to-thousands per year. They're often legal, often disclosed, and often overlooked.
Published 2026-04-25 · Last reviewed 2026-04-26 · methodology
California — Mello-Roos (Community Facilities Districts)
Authorized by the 1982 Mello-Roos Community Facilities Act.
Funds infrastructure (roads, schools, parks) for new developments. Bond debt is repaid by parcel-level annual special tax.
Typical impact: $500-3,500/year on top of the 1% Prop-13 base + ad valorem assessments.
Term: usually 25-40 years from bond issuance. After bonds mature, the tax disappears.
Disclosure: California requires a Mello-Roos disclosure document (Notice of Special Tax) at sale. Read it.
Florida — CDDs (Community Development Districts)
Common in master-planned communities (The Villages, Lakewood Ranch, many newer Orlando/Tampa subdivisions).
Two components: O&M (operations & maintenance — recurring) + Capital Debt Service (bond payback — finite term).
Impact: $1,500-5,000/year combined typical. Can exceed the base ad valorem property tax.
Disclosure: required on the listing per Florida statute, but easily missed in the noise of paperwork.
Texas — MUDs (Municipal Utility Districts) + PIDs
MUDs fund water/sewer/drainage in unincorporated areas (most Houston suburbs). Tax rate appears as a separate line on your tax bill.
PIDs (Public Improvement Districts) — assessment-based, similar to Mello-Roos. Common in Frisco, McKinney, other DFW exurbs.
Impact: a $400k home in a MUD can carry $1,500-3,000/year in MUD tax above the school + county rate.
How to find them before you buy
Pull the property tax bill (county assessor). Look for line items beyond the base school/county/city rate.
Ask the listing agent: 'Is this property in a Mello-Roos / CDD / MUD / PID? What's the annual amount, and when does the bond mature?'
California: request the Mello-Roos Notice of Special Tax. Florida: request the CDD disclosure. Texas: review the tax bill line-items.
If the seller can't or won't provide the data, your title company will surface it during the title search — but by then you've already invested in inspection + appraisal.
What zipradar shows
Property-tax effective millage at the ZIP level — the COUNTY base. See /topic/property-tax/[zip]/.
Special-district taxes are PARCEL-LEVEL (not ZIP-level), so they don't appear in our federation. Always pull the actual tax bill from the county assessor for the specific parcel.
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