Section 179 Deduction Calculator

Calculates the Section 179 expense deduction as Form 4562 Part I does, with the limits raised by the One Big Beautiful Bill Act: $2,500,000 for 2025 with a dollar-for-dollar phase-out above $4,000,000 of section 179 property (2025 Form 4562 instructions, Pub. 946), and $2,560,000 / $4,090,000 for 2026 (Rev. Proc. 2025-32 section 4.24). Applies the business income limit and reports the carryover. 2027 limits are not published yet (checked 2026-11-02) and the tool says so.

{
  "type": "object",
  "properties": {
    "tax_year": {
      "type": "integer",
      "minimum": 2025,
      "maximum": 2027,
      "description": "Tax year the property is placed in service: 2025 or 2026."
    },
    "total_section_179_property_cost": {
      "type": "number",
      "minimum": 0,
      "maximum": 100000000000,
      "description": "Total cost of all section 179 property placed in service in the year (Form 4562 line 2)."
    },
    "elected_cost": {
      "type": "number",
      "minimum": 0,
      "maximum": 100000000000,
      "description": "Amount you elect to expense. Defaults to the most allowed."
    },
    "business_taxable_income": {
      "type": "number",
      "minimum": -100000000000,
      "maximum": 100000000000,
      "description": "Taxable income from the active conduct of your trades or businesses, including wages (Form 4562 line 11). Leave out to skip the income limit."
    }
  },
  "required": [
    "tax_year",
    "total_section_179_property_cost"
  ],
  "additionalProperties": false,
  "$schema": "http://json-schema.org/draft-07/schema#"
}

Finds the special (bonus) depreciation rate under IRC 168(k) from the acquisition and placed-in-service dates and applies it after any Section 179 deduction. The One Big Beautiful Bill Act made it 100% permanently for property acquired after January 19, 2025 (written binding contract date), with an election to take 40% (60% for long production property and certain aircraft) in the first tax year ending after that date. Property acquired before January 20, 2025 keeps the TCJA phase-down: 40% if placed in service in 2025 (60% long production). Rules from IRS Notice 2026-11, the 2025 Form 4562 instructions and Pub. 946.

{
  "type": "object",
  "properties": {
    "acquired_date": {
      "type": "string",
      "pattern": "^\\d{4}-\\d{2}-\\d{2}$",
      "description": "Acquisition date, YYYY-MM-DD. Use the date a written binding contract was signed if earlier than delivery."
    },
    "placed_in_service_date": {
      "type": "string",
      "pattern": "^\\d{4}-\\d{2}-\\d{2}$",
      "description": "Date the property was placed in service, YYYY-MM-DD."
    },
    "depreciable_basis": {
      "type": "number",
      "minimum": 0,
      "maximum": 100000000000,
      "description": "Depreciable basis (business share of cost) in USD."
    },
    "section_179_deduction": {
      "type": "number",
      "minimum": 0,
      "maximum": 100000000000,
      "description": "Section 179 amount already taken on this property; bonus applies to what is left."
    },
    "long_production_or_aircraft": {
      "type": "boolean",
      "description": "True for long production period property or certain noncommercial aircraft."
    },
    "elect_reduced_rate": {
      "type": "boolean",
      "description": "True to elect 40% (60%) instead of 100% for property acquired after Jan 19, 2025 and placed in service in the first tax year ending after that date."
    },
    "elect_out": {
      "type": "boolean",
      "description": "True if you elect out of bonus depreciation for this class of property."
    }
  },
  "required": [
    "acquired_date",
    "placed_in_service_date",
    "depreciable_basis"
  ],
  "additionalProperties": false,
  "$schema": "http://json-schema.org/draft-07/schema#"
}

Returns the first-year write-off limits for a business vehicle by gross vehicle weight rating: passenger automobiles of 6,000 lb or less are held to the IRC 280F caps ($20,300 first year with bonus, $12,300 without, for 2026 per Rev. Proc. 2026-15; $20,200 / $12,200 for 2025 per Rev. Proc. 2025-16), heavy SUVs over 6,000 and up to 14,000 lb have a Section 179 cap of $31,300 (2025) or $32,000 (2026) with bonus depreciation for the rest, and vehicles over 14,000 lb or exempt designs have no vehicle cap. Applies the more-than-50% business use rule and scales by business use.

{
  "type": "object",
  "properties": {
    "tax_year": {
      "type": "integer",
      "minimum": 2025,
      "maximum": 2027,
      "description": "Year placed in service: 2025 or 2026."
    },
    "gvwr_lbs": {
      "type": "number",
      "minimum": 0,
      "maximum": 200000,
      "description": "Gross vehicle weight rating in pounds (driver door sticker)."
    },
    "cost": {
      "type": "number",
      "minimum": 0,
      "maximum": 100000000000,
      "description": "Vehicle cost in USD."
    },
    "business_use_percent": {
      "type": "number",
      "minimum": 0,
      "maximum": 100,
      "description": "Business use share, 0-100. Default 100."
    },
    "bonus_eligible": {
      "type": "boolean",
      "description": "False if bonus depreciation is not taken (elected out). Default true."
    },
    "exempt_from_suv_cap": {
      "type": "boolean",
      "description": "True for a 6,001-14,000 lb vehicle that seats more than nine behind the driver, has a cargo bed of at least 6 feet, or is an enclosed cargo van."
    }
  },
  "required": [
    "tax_year",
    "gvwr_lbs"
  ],
  "additionalProperties": false,
  "$schema": "http://json-schema.org/draft-07/schema#"
}

Calculates the exact monthly payment, total interest and first-year interest for an equipment, truck, tractor, RV, land, manufactured home, ATV, pontoon or other asset loan, and, for business assets, the after-tax cost: first-year tax saving from the Section 179 or bonus deduction plus deductible interest at your marginal rate, first-year net cash, and lifetime after-tax cost. Pair it with calculate_section_179 for the deduction amount.

{
  "type": "object",
  "properties": {
    "price": {
      "type": "number",
      "minimum": 0,
      "maximum": 100000000000,
      "description": "Purchase price in USD."
    },
    "down_payment": {
      "type": "number",
      "minimum": 0,
      "maximum": 100000000000,
      "description": "Down payment in USD. Default 0."
    },
    "apr_percent": {
      "type": "number",
      "minimum": 0,
      "maximum": 60,
      "description": "Annual percentage rate, e.g. 7.5."
    },
    "term_months": {
      "type": "integer",
      "minimum": 1,
      "maximum": 480,
      "description": "Loan term in months."
    },
    "asset_type": {
      "type": "string",
      "enum": [
        "equipment",
        "tractor",
        "semi_truck",
        "commercial_truck",
        "commercial_vehicle",
        "farm",
        "aircraft",
        "trailer",
        "rv",
        "motorcycle",
        "land",
        "manufactured_home",
        "atv",
        "utv",
        "pontoon",
        "other"
      ],
      "description": "Type of asset, used to link the matching calculator page."
    },
    "business_use_percent": {
      "type": "number",
      "minimum": 0,
      "maximum": 100,
      "description": "Business use share 0-100. Give this or marginal_tax_rate to get the after-tax cost."
    },
    "marginal_tax_rate": {
      "type": "number",
      "minimum": 0,
      "maximum": 0.6,
      "description": "Combined marginal tax rate as a decimal, e.g. 0.30."
    },
    "first_year_deduction": {
      "type": "number",
      "minimum": 0,
      "maximum": 100000000000,
      "description": "Section 179 plus bonus deduction taken in year 1. Defaults to the full business share of the price."
    }
  },
  "required": [
    "price",
    "apr_percent",
    "term_months"
  ],
  "additionalProperties": false,
  "$schema": "http://json-schema.org/draft-07/schema#"
}