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FLFlorida TaxCalculator

Methodology

By Bennett · Founder & editor
Reviewed

This page documents the assumptions and constants behind every Florida Tax Calculator estimate. If something on the site looks wrong, the answer to "how is this computed" should be on this page. If it isn't, that's a bug — flag it and I'll add it.

Federal income tax brackets (2026)

Calculators use 2026 ordinary-income brackets indexed forward from 2025 IRS values (Rev. Proc. 2024-40) using a conservative inflation factor. Single-filer brackets in use today:

  • 10% up to $12,000
  • 12% to $48,800
  • 22% to $104,100
  • 24% to $198,800
  • 32% to $252,500
  • 35% to $631,500
  • 37% above $631,500

Married-filing-jointly, head-of-household, and married-filing-separately brackets use the corresponding 2026 projections. Final 2026 figures get published by the IRS in late 2025; I update constants when the official release is available and log the change in the timeline below.

Standard deduction (2026)

  • Single / MFS: $15,800
  • MFJ: $31,600
  • Head of household: $23,700

FICA constants (2026)

  • Social Security: 6.2% up to the 2026 wage base of $181,800 (estimated from the 2025 base of $176,100)
  • Medicare: 1.45% on all wages, no cap
  • Additional Medicare: 0.9% on wages above $200,000 single / $250,000 MFJ / $125,000 MFS

Self-employment tax (Schedule SE)

SE tax = 15.3% (12.4% SS + 2.9% Medicare) applied to 92.35% of net self-employment earnings. Social Security portion capped at the 2026 wage base after counting any other W-2 wages for the same year. Half of total SE tax is deductible above the line on Form 1040. Additional Medicare 0.9% applies above the same single/MFJ thresholds, on combined SE base plus W-2 wages.

Bonus / supplemental withholding

Federal supplemental rate: 22% on bonuses up to $1,000,000 per employee per year, 37% on any portion above. FICA applied with proper YTD wage-cap handling. Florida adds 0% — there is no state supplemental rate.

Florida-specific rules

  • State personal income tax: 0%. The Florida Constitution prohibits a personal income tax without a constitutional amendment.
  • State sales tax: 6%, plus county discretionary surtaxes typically 0.5%–1.5%. Most groceries and prescription drugs exempt. Discretionary surtax applies only to the first $5,000 of any single transaction.
  • Estate tax: None. Florida has no state estate or inheritance tax.
  • Capital gains: no state-level tax. Federal long-term rates (0%, 15%, 20%) apply unchanged.
  • Property tax: county-level millage, generally 1.6%–2.2% before homestead exemption. Homestead exemption removes up to $50,000 from assessed value for owner-occupied primary residences. Save Our Homes caps annual increase in assessed value at 3% (or CPI, whichever is lower).

State comparison constants

For Florida-vs-X comparisons, I use 2025 published bracket structures from each state's Department of Revenue applied against income net of that state's standard deduction. NY+NYC layers the city resident surtax. These are simplified single-filer effective-rate calculations; they don't model credits, AMT, locality surtaxes beyond NYC, or filing-status interactions in full. They're close enough to size up a relocation decision; they aren't close enough to file with.

Sources I rely on

  • IRS Rev. Proc. 2024-40 — 2025 inflation-adjusted brackets and standard deductions, projected forward to 2026.
  • IRS supplemental withholding rules — 26 CFR §31.3402(g)-1.
  • IRS Notice (forthcoming) — 2026 Social Security wage base. Currently using SSA projections from the 2025 base.
  • Schedule SE instructions — for self-employment tax computation.
  • Florida Department of Revenue — state sales tax (6%) and county discretionary surtax tables.
  • Florida Statutes §220 — corporate income tax. Note: Florida has no individual income tax; no individual statute applies.
  • State Departments of Revenue (CA Franchise Tax Board, NY Tax & Finance, NJ Treasury, MA DOR, IL DOR, GA DOR) for comparison-state bracket structures.

Known limitations

  • Mid-year movers from a state with income tax — calculators don't allocate withholding pro-rata across the partial year.
  • Federal credits (CTC, EITC, premium tax credit, Saver's Credit, education credits) — not modeled.
  • Itemized deductions above the standard deduction — not modeled. For households with substantial mortgage interest plus state property tax (capped at $10,000 SALT), itemizing may shift the federal-tax line by several thousand dollars.
  • AMT — not modeled. Rare at typical W-2 incomes after TCJA but possible at very high incomes with unusual deduction profiles.
  • Multi-state income allocation — work physically performed in another state remains source-taxable there. Particularly relevant for NY remote workers under the convenience-of-the-employer rule.
  • Equity compensation (RSUs, ISOs, NSOs, ESPP, deferred compensation) — not modeled.
  • Roth 401(k) contributions — calculators model only pretax 401(k); Roth contributions don't reduce federal taxable income.
  • Property tax — handled qualitatively in editorial pages, not as a calculator output.

Update timeline

  • Sharpened SERP metadata across all calculator and guide pages. No math changes.
  • Updated 2026 federal brackets to IRS revised inflation factor; effective rates shifted within 0.1 points across most income bands.
  • Added Additional Medicare tax handling at the $200,000 single / $250,000 MFJ / $125,000 MFS thresholds. Prior versions occasionally under-counted the surtax for incomes that crossed the threshold mid-year.
  • Fixed self-employment tax base to apply 92.35% of net SE earnings before computing SS and Medicare portions, per Schedule SE.
  • Released initial 2026 projections — federal brackets indexed forward from 2025 IRS values; SS wage base set to $181,800 estimate.

Material errors get a dated entry in this log when I fix them. If you spot something I missed, the contact form in the footer is the fastest path. See also the About page for what this site is and isn't.