{
  "@context": "https://schema.org",
  "@type": "Dataset",
  "@id": "https://taxvalio.com/api/v1/us/quarterly-safe-harbor/2026.json",
  "name": "US Quarterly Estimated Tax safe-harbor + 2026 deadlines (IRC §6654)",
  "description": "IRC §6654(d) safe-harbor rule in machine-readable form. Avoid the underpayment penalty by paying the minimum of (a) 90% of current-year tax OR (b) 100% of prior-year tax — 110% if prior-year AGI > $150,000. Plus the four 2026 statutory due dates per §6654(c). Sufficient to recompute the annual safe-harbor minimum and per-quarter payment for any taxpayer profile.",
  "module": {
    "id": "us.2026.v1",
    "country": "US",
    "year": 2026,
    "version": 1,
    "label": "United States 2026"
  },
  "data": {
    "currentYearMultiplier": {
      "value": 0.9,
      "unit": "ratio",
      "description": "90% of current-year tax liability — one of the two §6654(d)(1) safe-harbor paths."
    },
    "priorYearBase": {
      "value": 1,
      "unit": "ratio",
      "description": "100% of prior-year tax — the default prior-year multiplier (AGI ≤ $150k)."
    },
    "priorYearHighEarnerMultiplier": {
      "value": 1.1,
      "unit": "ratio",
      "description": "110% of prior-year tax — applied when prior-year AGI > $150,000 per §6654(d)(1)(C)(i)."
    },
    "priorYearHighEarnerThreshold": {
      "value": 150000,
      "unit": "USD",
      "description": "AGI threshold that swaps the 100% rule for 110%."
    },
    "rule": "safeHarbor = min(currentYearEstimatedTax × 0.9, priorYearTax × priorYearMultiplier) where priorYearMultiplier = priorYearAgi > 150000 ? 1.1 : 1.0. Per-quarter payment = safeHarbor / 4.",
    "quarterlyDeadlines": [
      {
        "quarter": "Q1",
        "period": "Jan 1 – Mar 31, 2026",
        "dueDate": "2026-04-15",
        "citation": {
          "label": "IRC §6654",
          "url": "https://www.law.cornell.edu/uscode/text/26/6654",
          "effectiveYear": 2026,
          "readDate": "2026-04-20"
        }
      },
      {
        "quarter": "Q2",
        "period": "Apr 1 – May 31, 2026",
        "dueDate": "2026-06-15",
        "citation": {
          "label": "IRC §6654",
          "url": "https://www.law.cornell.edu/uscode/text/26/6654",
          "effectiveYear": 2026,
          "readDate": "2026-04-20"
        }
      },
      {
        "quarter": "Q3",
        "period": "Jun 1 – Aug 31, 2026",
        "dueDate": "2026-09-15",
        "citation": {
          "label": "IRC §6654",
          "url": "https://www.law.cornell.edu/uscode/text/26/6654",
          "effectiveYear": 2026,
          "readDate": "2026-04-20"
        }
      },
      {
        "quarter": "Q4",
        "period": "Sep 1 – Dec 31, 2026",
        "dueDate": "2027-01-15",
        "citation": {
          "label": "IRC §6654",
          "url": "https://www.law.cornell.edu/uscode/text/26/6654",
          "effectiveYear": 2026,
          "readDate": "2026-04-20"
        }
      }
    ]
  },
  "creator": {
    "@type": "Organization",
    "name": "TaxValio",
    "url": "https://taxvalio.com"
  },
  "license": "https://creativecommons.org/licenses/by/4.0/",
  "spatialCoverage": {
    "@type": "Country",
    "name": "United States"
  },
  "temporalCoverage": "2026",
  "inLanguage": "en",
  "isAccessibleForFree": true,
  "sameAs": [
    "https://taxvalio.com/us-quarterly-estimated-tax-calculator/"
  ]
}