{
  "$schema_note": "Single source of truth for PiggyMath 2026 federal tax figures. Each scalar/object has value + source metadata. Runtime still lives in assets/app.js — run: node tools/verify_tax_constants.mjs",
  "tax_year": 2026,
  "updated": "2026-08-13",
  "scalars": {
    "ss_wage_base": {
      "value": 184500,
      "unit": "USD",
      "source": "SSA contribution and benefit base (2026)",
      "source_url": "https://www.ssa.gov/oact/cola/cbb.html",
      "effective_from": "2026-01-01",
      "app_path": "TAX2026.ssWageBase"
    },
    "se_net_earnings_factor": {
      "value": 0.9235,
      "unit": "ratio",
      "source": "IRC §1402(a)(12) / Schedule SE (92.35%)",
      "source_url": "https://www.irs.gov/businesses/small-businesses-self-employed/self-employment-tax-social-security-and-medicare-taxes",
      "effective_from": "1990-01-01",
      "app_path": "TAX2026.seFactor"
    },
    "ss_rate_combined": {
      "value": 0.124,
      "unit": "rate",
      "source": "OASDI combined employer+employee rate",
      "source_url": "https://www.ssa.gov/oact/progdata/taxRates.html",
      "effective_from": "1990-01-01",
      "app_path": "TAX2026.ssRate"
    },
    "medicare_rate_combined": {
      "value": 0.029,
      "unit": "rate",
      "source": "HI (Medicare) combined rate — no wage base",
      "source_url": "https://www.ssa.gov/oact/progdata/taxRates.html",
      "effective_from": "1986-01-01",
      "app_path": "TAX2026.medicareRate"
    },
    "additional_medicare_rate": {
      "value": 0.009,
      "unit": "rate",
      "source": "IRC §3101(b)(2) Additional Medicare Tax",
      "source_url": "https://www.irs.gov/businesses/small-businesses-self-employed/questions-and-answers-for-the-additional-medicare-tax",
      "effective_from": "2013-01-01",
      "app_path": "TAX2026.addlMedicareRate"
    },
    "niit_rate": {
      "value": 0.038,
      "unit": "rate",
      "source": "IRC §1411 Net Investment Income Tax — not inflation-indexed",
      "source_url": "https://www.irs.gov/individuals/net-investment-income-tax",
      "effective_from": "2013-01-01",
      "app_path": "TAX2026.niitRate"
    },
    "corporate_rate": {
      "value": 0.21,
      "unit": "rate",
      "source": "IRC §11 flat corporate income tax rate",
      "source_url": "https://www.irs.gov/publications/p542",
      "effective_from": "2018-01-01",
      "app_path": "CORP_RATE"
    },
    "aca_cliff_fpl_pct": {
      "value": 400,
      "unit": "percent_of_FPL",
      "source": "Premium Tax Credit eligibility ceiling (post-ARPA sunset / OBBBA framing for 2026)",
      "source_url": "https://www.irs.gov/credits-deductions/individuals/premium-tax-credit",
      "effective_from": "2026-01-01",
      "app_path": "ACA_CLIFF"
    },
    "salt_cap_2026": {
      "value": 40400,
      "unit": "USD",
      "source": "OBBBA temporary SALT cap figure used on-site for 2026",
      "source_url": "https://www.irs.gov/",
      "effective_from": "2026-01-01",
      "app_path": "SALT_CAP_2026",
      "notes": "Confirm against final IRS guidance before treating as filing advice."
    },
    "ctc_per_child": {
      "value": 2200,
      "unit": "USD",
      "source": "Child Tax Credit amount for 2026 (indexed / statute as implemented)",
      "source_url": "https://www.irs.gov/credits-deductions/individuals/child-tax-credit",
      "effective_from": "2026-01-01",
      "app_path": "CTC2026.perChild"
    },
    "ctc_refundable_cap": {
      "value": 1700,
      "unit": "USD",
      "source": "Additional Child Tax Credit refundable cap 2026",
      "source_url": "https://www.irs.gov/credits-deductions/individuals/child-tax-credit",
      "effective_from": "2026-01-01",
      "app_path": "CTC2026.refundableCap"
    },
    "ctc_earned_floor": {
      "value": 2500,
      "unit": "USD",
      "source": "ACTC earned-income floor IRC §24(d)",
      "source_url": "https://www.irs.gov/credits-deductions/individuals/child-tax-credit",
      "effective_from": "2018-01-01",
      "app_path": "CTC2026.earnedFloor"
    },
    "odc_per_dependent": {
      "value": 500,
      "unit": "USD",
      "source": "Credit for Other Dependents",
      "source_url": "https://www.irs.gov/credits-deductions/individuals/child-tax-credit",
      "effective_from": "2018-01-01",
      "app_path": "CTC2026.odc"
    },
    "qbi_min_deduction": {
      "value": 400,
      "unit": "USD",
      "source": "OBBBA §199A minimum deduction floor (when QBI ≥ $1,000)",
      "source_url": "https://www.irs.gov/newsroom/qualified-business-income-deduction",
      "effective_from": "2026-01-01",
      "app_path": "QBI_2026.minDeduction"
    },
    "qbi_min_qbi": {
      "value": 1000,
      "unit": "USD",
      "source": "Minimum QBI to unlock §199A floor deduction",
      "source_url": "https://www.irs.gov/newsroom/qualified-business-income-deduction",
      "effective_from": "2026-01-01",
      "app_path": "QBI_2026.minQbi"
    },
    "mileage_h1_per_mile": {
      "value": 0.725,
      "unit": "USD_per_mile",
      "source": "IRS standard mileage rate Jan–Jun 2026",
      "source_url": "https://www.irs.gov/tax-professionals/standard-mileage-rates",
      "effective_from": "2026-01-01",
      "effective_to": "2026-06-30",
      "app_path": "MILEAGE2026.h1"
    },
    "mileage_h2_per_mile": {
      "value": 0.76,
      "unit": "USD_per_mile",
      "source": "IRS standard mileage rate Jul–Dec 2026 (Announcement 2026-11)",
      "source_url": "https://www.irs.gov/tax-professionals/standard-mileage-rates",
      "effective_from": "2026-07-01",
      "effective_to": "2026-12-31",
      "app_path": "MILEAGE2026.h2"
    },
    "solo_elective_deferral": {
      "value": 24500,
      "unit": "USD",
      "source": "IRC §402(g) elective deferral limit 2026",
      "source_url": "https://www.irs.gov/retirement-plans/plan-participant-employee/retirement-topics-401k-and-profit-sharing-plan-contribution-limits",
      "effective_from": "2026-01-01",
      "app_path": "SOLO_2026.deferral"
    },
    "solo_catch_up_50": {
      "value": 8000,
      "unit": "USD",
      "source": "Age 50+ catch-up contribution 2026",
      "source_url": "https://www.irs.gov/retirement-plans/plan-participant-employee/retirement-topics-catch-up-contributions",
      "effective_from": "2026-01-01",
      "app_path": "SOLO_2026.catchUp"
    },
    "solo_super_catch_up": {
      "value": 11250,
      "unit": "USD",
      "source": "Ages 60–63 higher catch-up 2026 (SECURE 2.0)",
      "source_url": "https://www.irs.gov/retirement-plans/plan-participant-employee/retirement-topics-catch-up-contributions",
      "effective_from": "2026-01-01",
      "app_path": "SOLO_2026.superCatchUp"
    },
    "solo_annual_additions": {
      "value": 72000,
      "unit": "USD",
      "source": "IRC §415(c) annual additions limit 2026",
      "source_url": "https://www.irs.gov/retirement-plans/plan-participant-employee/retirement-topics-401k-and-profit-sharing-plan-contribution-limits",
      "effective_from": "2026-01-01",
      "app_path": "SOLO_2026.additions"
    },
    "solo_compensation_cap": {
      "value": 360000,
      "unit": "USD",
      "source": "IRC §401(a)(17) compensation cap 2026",
      "source_url": "https://www.irs.gov/retirement-plans/plan-participant-employee/retirement-topics-401k-and-profit-sharing-plan-contribution-limits",
      "effective_from": "2026-01-01",
      "app_path": "SOLO_2026.compCap"
    },
    "hsa_self_only": {
      "value": 4400,
      "unit": "USD",
      "source": "HSA contribution limit self-only 2026",
      "source_url": "https://www.irs.gov/publications/p969",
      "effective_from": "2026-01-01",
      "app_path": "HSA_2026.selfOnly"
    },
    "hsa_family": {
      "value": 8750,
      "unit": "USD",
      "source": "HSA contribution limit family 2026",
      "source_url": "https://www.irs.gov/publications/p969",
      "effective_from": "2026-01-01",
      "app_path": "HSA_2026.family"
    },
    "hsa_catch_up": {
      "value": 1000,
      "unit": "USD",
      "source": "HSA catch-up age 55+",
      "source_url": "https://www.irs.gov/publications/p969",
      "effective_from": "2004-01-01",
      "app_path": "HSA_2026.catchUp"
    },
    "ira_limit": {
      "value": 7500,
      "unit": "USD",
      "source": "Traditional/Roth IRA contribution limit 2026",
      "source_url": "https://www.irs.gov/retirement-plans/ira-deduction-limits",
      "effective_from": "2026-01-01",
      "app_path": "IRA2026.limit"
    },
    "ira_catch_up": {
      "value": 1100,
      "unit": "USD",
      "source": "IRA catch-up age 50+ 2026",
      "source_url": "https://www.irs.gov/retirement-plans/ira-deduction-limits",
      "effective_from": "2026-01-01",
      "app_path": "IRA2026.catchUp"
    },
    "section_179_cap": {
      "value": 2560000,
      "unit": "USD",
      "source": "§179 expensing dollar limitation 2026 (as implemented)",
      "source_url": "https://www.irs.gov/newsroom/irs-issues-guidance-on-section-179-expenses-and-special-depreciation-allowance",
      "effective_from": "2026-01-01",
      "app_path": "S179.cap"
    },
    "section_179_phaseout_start": {
      "value": 4090000,
      "unit": "USD",
      "source": "§179 investment phase-out threshold 2026",
      "source_url": "https://www.irs.gov/newsroom/irs-issues-guidance-on-section-179-expenses-and-special-depreciation-allowance",
      "effective_from": "2026-01-01",
      "app_path": "S179.phaseOutStart"
    },
    "section_179_suv_cap": {
      "value": 32000,
      "unit": "USD",
      "source": "§179 SUV / heavy vehicle cap 2026",
      "source_url": "https://www.irs.gov/newsroom/irs-issues-guidance-on-section-179-expenses-and-special-depreciation-allowance",
      "effective_from": "2026-01-01",
      "app_path": "S179.suvCap"
    },
    "form_1099k_federal_amount": {
      "value": 20000,
      "unit": "USD",
      "source": "Federal 1099-K reporting threshold amount (OBBBA restore)",
      "source_url": "https://www.irs.gov/businesses/understanding-your-form-1099-k",
      "effective_from": "2026-01-01",
      "app_path": "FORM1099K.federal.amount"
    },
    "form_1099k_federal_tx": {
      "value": 200,
      "unit": "transactions",
      "source": "Federal 1099-K reporting threshold transaction count",
      "source_url": "https://www.irs.gov/businesses/understanding-your-form-1099-k",
      "effective_from": "2026-01-01",
      "app_path": "FORM1099K.federal.tx"
    }
  },
  "objects": {
    "std_deduction": {
      "value": { "single": 16100, "mfj": 32200, "hoh": 24150, "mfs": 16100 },
      "source": "IRS Rev. Proc. 2025-32 — 2026 standard deduction",
      "source_url": "https://www.irs.gov/pub/irs-drop/rp-25-32.pdf",
      "effective_from": "2026-01-01",
      "app_path": "TAX2026.stdDeduction"
    },
    "addl_medicare_threshold": {
      "value": { "single": 200000, "mfj": 250000, "hoh": 200000, "mfs": 125000 },
      "source": "IRC §3101(b)(2) — not inflation-indexed",
      "source_url": "https://www.irs.gov/businesses/small-businesses-self-employed/questions-and-answers-for-the-additional-medicare-tax",
      "effective_from": "2013-01-01",
      "app_path": "TAX2026.addlThreshold"
    },
    "niit_threshold": {
      "value": { "single": 200000, "mfj": 250000, "hoh": 200000, "mfs": 125000 },
      "source": "IRC §1411 — not inflation-indexed",
      "source_url": "https://www.irs.gov/individuals/net-investment-income-tax",
      "effective_from": "2013-01-01",
      "app_path": "TAX2026.niitThreshold"
    },
    "ctc_phaseout": {
      "value": { "single": 200000, "mfj": 400000, "hoh": 200000, "mfs": 200000 },
      "source": "IRC §24(b)(2) MAGI phaseout thresholds",
      "source_url": "https://www.irs.gov/credits-deductions/individuals/child-tax-credit",
      "effective_from": "2018-01-01",
      "app_path": "CTC2026.phase"
    },
    "qbi_threshold": {
      "value": { "single": 201750, "mfj": 403500, "hoh": 201750, "mfs": 201775 },
      "source": "Rev. Proc. 2025-32 §4.26 / OBBBA §199A thresholds",
      "source_url": "https://www.irs.gov/pub/irs-drop/rp-25-32.pdf",
      "effective_from": "2026-01-01",
      "app_path": "QBI_2026.threshold"
    },
    "qbi_phasein_range": {
      "value": { "single": 75000, "mfj": 150000, "hoh": 75000, "mfs": 75000 },
      "source": "OBBBA §199A phase-in ranges",
      "source_url": "https://www.irs.gov/newsroom/qualified-business-income-deduction",
      "effective_from": "2026-01-01",
      "app_path": "QBI_2026.range"
    },
    "federal_brackets": {
      "value": {
        "single": [[12400, 0.1], [50400, 0.12], [105700, 0.22], [201775, 0.24], [256225, 0.32], [640600, 0.35], [null, 0.37]],
        "mfj": [[24800, 0.1], [100800, 0.12], [211400, 0.22], [403550, 0.24], [512450, 0.32], [768700, 0.35], [null, 0.37]],
        "hoh": [[17700, 0.1], [67450, 0.12], [105700, 0.22], [201775, 0.24], [256200, 0.32], [640600, 0.35], [null, 0.37]],
        "mfs": [[12400, 0.1], [50400, 0.12], [105700, 0.22], [201775, 0.24], [256225, 0.32], [384350, 0.35], [null, 0.37]]
      },
      "notes": "Each pair is [top_of_bracket_or_null_for_top, rate]. null serializes Infinity used in app.js.",
      "source": "IRS Rev. Proc. 2025-32 Tables 1–4",
      "source_url": "https://www.irs.gov/pub/irs-drop/rp-25-32.pdf",
      "effective_from": "2026-01-01",
      "app_path": "TAX2026.brackets"
    },
    "ltcg_brackets": {
      "value": {
        "single": [[0, 0], [49450, 0.15], [545500, 0.2]],
        "mfj": [[0, 0], [98900, 0.15], [613700, 0.2]],
        "hoh": [[0, 0], [66200, 0.15], [579600, 0.2]],
        "mfs": [[0, 0], [49450, 0.15], [306850, 0.2]]
      },
      "source": "Rev. Proc. 2025-32 §4.03 — maximum zero / 15% rate amounts",
      "source_url": "https://www.irs.gov/pub/irs-drop/rp-25-32.pdf",
      "effective_from": "2026-01-01",
      "app_path": "LTCG_2026"
    },
    "fpl_2025_for_coverage_2026": {
      "value": {
        "contiguous": { "base": 15650, "add": 5500 },
        "alaska": { "base": 19550, "add": 6880 },
        "hawaii": { "base": 17990, "add": 6330 }
      },
      "source": "HHS 2025 poverty guidelines (govern 2026 coverage year PTC)",
      "source_url": "https://aspe.hhs.gov/topics/poverty-economic-mobility/poverty-guidelines",
      "effective_from": "2025-01-15",
      "app_path": "FPL_2025"
    },
    "applicable_percentage_2026": {
      "value": [
        [0, 133, 2.1, 2.1],
        [133, 150, 3.14, 4.19],
        [150, 200, 4.19, 6.6],
        [200, 250, 6.6, 8.44],
        [250, 300, 8.44, 9.96],
        [300, 400, 9.96, 9.96]
      ],
      "notes": "[lo_fpl_pct, hi_fpl_pct, pct_in, pct_fin] — linear within band (Rev. Proc. 2025-25)",
      "source": "IRS Rev. Proc. 2025-25 applicable percentage table",
      "source_url": "https://www.irs.gov/pub/irs-drop/rp-25-25.pdf",
      "effective_from": "2026-01-01",
      "app_path": "APPL_PCT_2026"
    },
    "hsa_hdhp_limits": {
      "value": {
        "minDeductible": { "selfOnly": 1700, "family": 3400 },
        "oopMax": { "selfOnly": 8500, "family": 17000 }
      },
      "source": "HDHP deductible / OOP limits for HSA eligibility 2026",
      "source_url": "https://www.irs.gov/publications/p969",
      "effective_from": "2026-01-01",
      "app_path": "HSA_2026.minDeductible|HSA_2026.oopMax"
    },
    "ira_roth_phaseout": {
      "value": { "single": [153000, 168000], "mfj": [242000, 252000] },
      "source": "Roth IRA MAGI phase-out range 2026",
      "source_url": "https://www.irs.gov/retirement-plans/amount-of-roth-ira-contributions-that-you-can-make-for-2026",
      "effective_from": "2026-01-01",
      "app_path": "IRA2026.roth"
    },
    "ira_trad_covered_phaseout": {
      "value": { "single": [81000, 91000], "mfj": [129000, 149000] },
      "source": "Traditional IRA deduction phase-out when covered by workplace plan 2026",
      "source_url": "https://www.irs.gov/retirement-plans/ira-deduction-limits",
      "effective_from": "2026-01-01",
      "app_path": "IRA2026.tradCovered"
    },
    "estimated_tax_deadlines_ty2026": {
      "value": [
        { "quarter": "Q1", "due": "2026-04-15", "income_window": "2026-01-01/2026-03-31" },
        { "quarter": "Q2", "due": "2026-06-15", "income_window": "2026-04-01/2026-05-31" },
        { "quarter": "Q3", "due": "2026-09-15", "income_window": "2026-06-01/2026-08-31" },
        { "quarter": "Q4", "due": "2027-01-15", "income_window": "2026-09-01/2026-12-31" }
      ],
      "source": "IRS Form 1040-ES estimated tax due dates",
      "source_url": "https://www.irs.gov/businesses/small-businesses-self-employed/estimated-taxes",
      "effective_from": "2026-01-01",
      "app_path": "icsDownload events / quarterly-tax-deadlines"
    }
  },
  "primary_sources": [
    {
      "id": "rp-2025-32",
      "label": "IRS Rev. Proc. 2025-32 — 2026 inflation adjustments",
      "url": "https://www.irs.gov/pub/irs-drop/rp-25-32.pdf"
    },
    {
      "id": "rp-2025-25",
      "label": "IRS Rev. Proc. 2025-25 — PTC applicable percentages",
      "url": "https://www.irs.gov/pub/irs-drop/rp-25-25.pdf"
    },
    {
      "id": "ssa-cbb-2026",
      "label": "SSA 2026 contribution and benefit base",
      "url": "https://www.ssa.gov/oact/cola/cbb.html"
    },
    {
      "id": "irs-estimated-taxes",
      "label": "IRS — Estimated Taxes",
      "url": "https://www.irs.gov/businesses/small-businesses-self-employed/estimated-taxes"
    }
  ]
}