Mortgage Decisioning

Modern mortgage underwriting. ATR/QM enforced automatically.

AltFiScore handles every mortgage decision: ATTOM property valuation, alternative-data income verification, federal QM rules, occupancy adjustments, and PMI calculations — in under 500ms per decision.

Get sandbox access See QM compliance

POST /v1/decisions/mortgage

412ms

Yes

DTI

38%

LTV

80%

Loan amount

6.85% APR · 30yr fixed

$480,000

$3,144/mo P&I · no PMI required

ATR / QM checks

✓ DTI 38% (under 43% QM cap)

✓ Income verified via Argyle

✓ ATTOM property value $600K confirmed

✓ 2 months reserves verified

✓ QM safe harbor · ✓ TRID disclosures · ✓ ECOA compliant

The problem

Mortgage underwriting still takes 30 days. Borrowers want answers in minutes.

Income calculations done in spreadsheets. Property valuations weeks behind market. Manual ATR documentation requiring 8 separate factors per file. Result: highly qualified borrowers walk to non-bank lenders who decide faster — even at worse rates.

21 days

Industry average mortgage decision time. AltFiScore returns the same decision with full QM documentation in 412ms.

Modern alt data decisioning

Eight ATR factors. Verified data. Auto-documented.

Every AltFiScore mortgage decision automatically documents all 8 ATR factors (income, employment, assets, debt, DTI, credit, residual income, alternative payments) using live data from Argyle, Plaid, and ATTOM. QM safe harbor or QM rebuttable presumption flagged on every response.

Argyle

Verified W-2 income

Direct payroll provider integration — no pay stub OCR, no tax transcript chasing. Documents two of the 8 ATR factors automatically.

Plaid

Reserve months

Live checking/savings balances calculate true reserve months. Surfaces wealth bureau data misses entirely.

Plaid

Existing debt obligations

Real-time DTI from actual recurring debits. More accurate than bureau-reported minimums on credit cards.

ATTOM

Subject property valuation

Independent property value from public records. Used for LTV calculation. Subject property data NEVER feeds borrower score (fraud prevention).

ATTOM

Existing home equity

For borrowers selling their current home, ATTOM data calculates available equity for down payment — separately from subject property.

AltFiScore

Occupancy adjustment

Primary residence (0bps) / second home (+25bps) / investment (+50bps) applied automatically to base rate.

Decisioning details

Rate bands and policy thresholds

Configurable rate bands per tenant. Federal compliance caps applied automatically. All policy decisions are versioned, reproducible, and audit-logged.

Grade	Score range	APR
A+	880–1000	6.25%
A	820–879	6.50%
B	740–819	6.85%
C	660–739	7.50%
D	300–659	8.50%

Federal compliance caps

QM Rule: 43% DTI cap (ATR safe harbor)
FHA minimum credit score: 580
Conforming loan limit (2026): $766,550
High-cost area limit: $1,149,825
PMI required when LTV exceeds 80%

Integration

One endpoint. JSON in, JSON out.

Idempotent. Versioned. TILA disclosures and FCRA codes built in. Sandbox tenant for testing, production tenant when you're ready.

1Sign up for a sandbox tenant
2POST to /v1/decisions/mortgage with consumer + loan + property
3AltFiScore pulls ATTOM property data automatically
4Argyle income verification triggers if not already on file
5Receive decision with QM determination + full ATR documentation

POST /v1/decisions/mortgage

curl -X POST 'https://api.altfiscore.com/v1/decisions/mortgage' \
  -H 'Authorization: Bearer altfi_live_YOUR_KEY' \
  -H 'Content-Type: application/json' \
  -d '{
    "consumer": { "first_name": "Elena", "last_name": "Rodriguez", ... },
    "loan": {
      "loan_amount": 480000,
      "term_months": 360,
      "sub_type": "conforming_30yr_fixed",
      "occupancy": "primary"
    },
    "property": {
      "address": "423 Beacon St",
      "city": "Brookline",
      "state": "MA",
      "zip": "02446",
      "property_type": "single_family",
      "purchase_price": 600000
    }
  }'

← Response · 200 OK

{
  "decision_id": "f8b2...",
  "status": "complete",
  "outcome": "approved",
  "score_at_decision": 768,
  "loan_amount": "480000.00",
  "recommended_apr": "6.85",
  "term_months": 360,
  "estimated_monthly_pi": "3144.42",
  "ltv_pct": 80.0,
  "dti_pct": 38.0,
  "qm_compliant": true,
  "qm_safe_harbor": true,
  "pmi_required": false,
  "attom_property_value": "600000.00",
  "occupancy_adjustment_bps": 0,
  "evaluation_details": {
    "ato_check": "passed",
    "income_verified_via": "argyle",
    "reserves_months": 2.1,
    "atr_factors_documented": 8
  }
}

Compliance

Built for compliance teams.

Every decision is versioned, reproducible, and audit-logged. Adverse action codes follow ECOA Regulation B. Disclosures meet TILA Reg Z.

ATR / QM Rule

All 8 Ability-to-Repay factors documented automatically. QM safe harbor flagged when DTI < 43% and other QM requirements met.

RESPA / TRID

Loan Estimate generated within 3 business days. Closing Disclosure 3 days before consummation.

TILA Reg Z

APR calculated correctly across all closing costs. HOEPA high-cost mortgage flagging built in.

HMDA

Home Mortgage Disclosure Act data points captured automatically for annual reporting.

ECOA Reg B

Adverse action notices generated with FCRA-compliant reason codes for all declined or referred decisions.

FHA Minimums

FHA loans automatically enforce 580 minimum credit score and 3.5% minimum down payment.

Modern mortgage decisioning. 30 seconds, not 30 days.

Test the full QM + ATR pipeline with sample applications across primary / second home / investment property scenarios.

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