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Mortgage Lending Educational Guides

Plain-English resources explaining federal mortgage disclosure rules, underwriting definitions, and how to interpret government lending data.

Understanding HMDA Data: A Plain-English Guide

Learn what the Home Mortgage Disclosure Act is, which lenders are required to report, what kinds of loans are tracked in the Loan Application Register, and what public records can and cannot tell us about mortgage credit.

Category: Regulatory Overview & Public Records

Mortgage Denial Reasons Explained

A detailed breakdown of the nine official HMDA adverse action categories—including Debt-to-Income, Credit History, and Collateral—how up to four reasons are reported per loan, and why a denial reason is rarely a sole isolated cause.

Category: Adverse Action Codes & Underwriting Factors

Methodology & Disclosures

Credit Decision Denominator Rule: Approval and denial rates are calculated strictly among actionable applications reaching a formal credit underwriting decision (Actions 1, 2, and 3: loan originated, approved but not accepted, denied). Applications withdrawn by borrower (Action 4) and closed for incompleteness (Action 5) are tracked in the broader Consumer Mortgage Universe for market completeness but excluded from credit decision rates as no underwriting decision occurred.

Official Data Source & Freeze Date: Official Home Mortgage Disclosure Act (HMDA) records published by the Federal Financial Institutions Examination Council (FFIEC) and Consumer Financial Protection Bureau (CFPB). Primary analysis uses the 2025 Snapshot National Loan-Level Dataset (frozen June 2, 2026); historical baseline uses the 2024 One-Year National Loan-Level Dataset (frozen June 2, 2026).

Public Interest Commitment: OpenFileData does not sell mortgage leads, lender placements, paid rankings, or individualized mortgage recommendations.

For complete technical formulas, SQL implementations, and data definitions, read the full Mortgage Lending Methodology Specification.