--- title: "Fannie Mae & Freddie Mac single-family loan-level data" description: >- How the GSE single-family loan-level acquisition and performance datasets are structured and accessed, why a pipeline cannot pull them no-key (both are free but registration-gated behind a click-through), the acquisition vs performance split, the pipe-delimited vs CSV format difference, and the quarterly vintages. sidebar: label: Fannie / Freddie loan-level order: 61 tags: [mortgages, housing, credit, loan-level, panel-data, free, academic, data:fannie-freddie] --- :::note[Free, but registration-gated and not exercised here] The GSE single-family loan-level datasets are **free** (no fee, including for academic use), but bulk download from both Fannie Mae and Freddie Mac requires a **no-cost account and a click-through terms acceptance**. The public landing portals are reachable (HTTP 200), but the data files sit behind the login wall, so the end-to-end pull was **not** exercised from this session. The page therefore carries **no provenance badge**: it documents the datasets and the access path. A researcher registers once (free) and downloads directly. ::: **The Fannie Mae and Freddie Mac single-family loan-level datasets** are the two government-sponsored enterprises' public releases of acquisition and monthly performance records for the single-family mortgages they bought. Each loan has origination characteristics (FICO, LTV, DTI, rate, term, purpose, geography) and a monthly performance history (delinquency status, prepayment, default, losses). They are the standard free microdata for US mortgage credit-risk and performance research. Used in, for example, [Rehbein & Rother (2025)](/wiki/papers/rfs/2025/rehbein-social-connectedness-bank-lending-2025/), where 1.27 million GSE 30-year fixed-rate mortgages (2000 to 2008 originations, observed to 2018) supply loan-level LTV, rate, delinquency, and default. - **Cost:** free (no fee; free account and terms acceptance required to download). - **API key:** none (bulk file download behind a registration portal). - **Coverage:** Freddie covers roughly 55 million mortgages originated from 1999 through the latest quarterly cutoff; Fannie's window is comparable. Both append new origination quarters over time. - **Granularity:** one acquisition/origination row per loan, plus monthly performance rows per loan. - **Portals (browser):** Fannie Data Dynamics ยท Freddie via Clarity Data Intelligence ## Access Both GSEs publish the data through a free registration portal. There is no anonymous direct link to the bulk files. - **Fannie Mae** distributes the Single-Family Loan Performance Data through Data Dynamics. After a free account and terms acceptance, the portal offers a one-click download of the full Acquisition file and the full Performance file, in CSV. - **Freddie Mac** distributes the Single Family Loan-Level Dataset through Clarity Data Intelligence. After a free sign-in (the data is free for non-commercial and academic use), the download page offers the full dataset, the Standard dataset by year, the Non-Standard dataset, sample files, and an RPL mapping file. Files are pipe-delimited. The public documentation (user guides, file-layout and data-dictionary PDFs, FAQs) is generally readable without an account; the loan-level files and even the sample files are behind the login. ## Gotchas (the ones that bite pipelines) - **Two file types per GSE, joined on the loan id.** Acquisition (one static row per loan, captured at origination) and Performance (one row per loan per month). Do not expect a single combined table; the performance file is the large one. - **Format differs between the two GSEs.** Freddie's files are pipe-delimited (`|`), no header, with a fixed column order set by the layout document. Fannie's Data Dynamics export is CSV. Column order, field set, and missing-value conventions differ, so do not reuse one schema for the other. - **Click-through terms, so no anonymous fetch.** An automated pull must carry a session cookie obtained after accepting the terms; there is no static URL to the zips. Plan for a one-time human registration. - **Quarterly vintages that grow.** Acquisition files are partitioned by origination quarter and new quarters are appended over time, so any hardcoded "latest quarter" logic rots. Record the vintage you pulled. - **Freddie Standard vs Non-Standard.** The Non-Standard dataset adds loans excluded from Standard (for example certain modified, ARM, or balloon loans); the RPL mapping file tracks reperforming loans. Choose deliberately rather than mixing them. - **Scale.** Tens of millions of loans and a monthly panel on top; the performance files are tens of gigabytes uncompressed. Stream or chunk; do not load whole. - **Host bot-blocking on top of the login.** The Fannie capitalmarkets host returns HTTP 403 to automated requests even before the login, so scripted navigation needs a real browser session, not just an authenticated cookie. ## Reference | Field | Value | |-------|-------| | Fannie portal | Data Dynamics (`capitalmarkets.fanniemae.com/tools-applications/data-dynamics`) | | Freddie portal | Clarity Data Intelligence (`freddiemac.com/research/datasets/sf-loanlevel-dataset`) | | File types | Acquisition (per loan) + Performance (per loan per month) | | Fannie format | CSV | | Freddie format | Pipe-delimited, no header | | Freddie coverage | ~55M loans, 1999 to latest quarterly cutoff | | Key required | No key, but free registration + terms acceptance | ## Citation Cite each GSE dataset separately: Fannie Mae, "Single-Family Loan Performance Data," and Freddie Mac, "Single Family Loan-Level Dataset," each with the vintage (origination-quarter range and performance cutoff) and retrieval date. Note in a methods appendix that access required free registration, since the files are not anonymously downloadable.