What the Zionsville schools referendum would do to your property tax bill

SEA 1 deductions. For a homestead, the $48,000 standard deduction shrinks each year and the supplemental deduction grows, per the schedule certified by the Indiana DLGF. Taxable value = (gross AV − standard deduction) × (1 − supplemental %). Non‑homestead residential (2% cap) property gets SEA 1's smaller new deduction, phasing from 6% to 33.4%.

Pay year	Standard deduction	Supplemental	Ref. rate if it fails	Ref. rate if it passes

Tax caps and credit. Non‑referendum taxes are capped at 1% of gross AV (2% for non‑homestead residential). Referendum taxes sit outside the cap. SEA 1 then subtracts a homestead credit of 10% of the non‑referendum bill, up to $300; by law the credit does not apply to referendum taxes.

Referendum rates. The year‑by‑year rates (27.06¢ in 2027 rising to the 41.28¢ maximum in 2034) are the projections built into the district's official calculator at localtaxcalculator.com, which is designed to hold the referendum's dollar collections roughly level as SEA 1 shrinks taxable values. The board sets the actual rate annually and can go lower (not higher) than the maximum. If the referendum fails, the current 24.44¢ rate continues through 2027 and then expires. Zionsville also has a separate 9.89¢ referendum debt rate (for buildings) that is unaffected by this vote and is included in both scenarios.

Old‑law line. What the bill would have been had SEA 1 never passed: $48,000 standard deduction, 35% supplemental deduction (25% on value above $600,000), no credit, and the existing 24.44¢ referendum renewed at its current rate.

Validation status. The shared deduction and ballot-rounding rules have automated checks. District projections and total-bill assumptions remain subject to source review; matching a ballot example does not validate a future total bill.

Not modeled. Changes to the county, city, township or library rates; the over‑65 and disabled‑veteran credits; property‑specific abatements; and any future reassessment beyond the growth option above.