US Geography Crosswalk: ZCTA, County, Place, Metro Area and State (CSV, JSON, SQLite)

← All Open reference data, cleaned and documented

About this data pack

The U.S. Census Bureau publishes everything you need to map ZIP-code-like areas to counties, places, states and metro areas, but it is spread across four different products, with different delimiters, vintages and key formats. This pack is that work done once: the 2026 Gazetteer, the 2020 reference code lists, the 2020 ZCTA relationship files and the OMB July 2023 metro/micro delineation joined into one keyed model, with every column documented.

You get a ready-to-use table (one row per ZCTA/county overlap, with county name, state, metro area and share of the ZCTA's land already attached), a one-row-per-ZCTA table with its primary county, state, place and metro area, and the normalised building blocks behind them. FIPS codes and ZCTAs are stored as zero-padded text in every format, so 00601 never turns into 601. Square metres are kept as published and square miles are added. Every column has a type, a source file and a description, and the build is scripted and reproducible.

ZCTAs are Census approximations, not USPS ZIP Codes. This pack contains no USPS data and is not official or endorsed by the Census Bureau or any other agency. It is cleaned and compiled by Quietcog from public data.

What you get

• 10 tables, 253,503 rows: states, counties, places, ZCTAs, CBSAs and the county/place/ZCTA relationships
• zcta_county_flat: one ready-to-use crosswalk row per ZCTA/county overlap with names, state, metro area and percent of land
• Primary county, state, place and metro area for every ZCTA, assigned by largest land overlap (rule documented)
• FIPS/GEOID/ZCTA kept as zero-padded text; UTF-8; consistent nulls; same data in CSV, JSON and SQLite
• Data dictionary for every column (type, source file, description), row counts, caveats and validation report included
• 145/145 automated checks passed: no duplicate keys, every foreign key resolves, row counts match across formats
• Public-domain Census sources; no attribution to us required; one price, no subscription

What is included in the download

• csv/ (one file per table), json/ (one file per table), us-geography-crosswalk.sqlite (all tables, with the data dictionary inside)
• README.md (quick start, data dictionary for every column, sources and vintages, cleaning steps, caveats)
• DATA_DICTIONARY.csv, VALIDATION.txt, SOURCES.lock.json (sha256 of every raw source file)
• LICENSE_AND_ATTRIBUTION.txt (each source's licence, quoted from its page), CHANGELOG.md, VERSION
• reproduce/ (the Python scripts that built this edition from the public source URLs)

Free sample (about 50 rows per table, zip, no purchase needed)

Questions

• Are these USPS ZIP Codes? No. ZCTAs are statistical areas the Census Bureau builds to approximate ZIP Code areas. They are not USPS ZIP Codes and can differ from them; some ZIP Codes have no ZCTA. The pack says so on every page of its documentation and contains no USPS data.
• Is this official Census data? No. It is built from public Census Bureau files, cleaned and joined by Quietcog. It is not produced, certified or endorsed by the Census Bureau.
• Why not just download the Census files? You can; they are free. This pack saves the cleaning and joining: four products with different delimiters, vintages and keys, a byte-order mark in the relationship files, Connecticut's county/planning-region mismatch, and the overlap shares and primary-county logic. It also comes with SQLite and a data dictionary.
• Which vintage? Names and areas: Gazetteer 2026. ZCTA relationships and place lists: 2020 census geography. Metro/micro areas: OMB July 2023 delineation. The README explains where these differ (notably Connecticut).
• What formats? CSV, JSON and a SQLite database, with identical contents. Everything is UTF-8.
• Do I need to credit anyone? No attribution is required. Suggested source lines are in LICENSE_AND_ATTRIBUTION.txt.
• Can I use it commercially? Yes, in your own products, apps and analyses. You may not resell or republish the pack itself as a data product. The source data stay public domain.
• Refunds? Within 14 days, see the refund policy.

Quietcog is the seller. Not official, not endorsed by the U.S. Census Bureau, USPS, OurAirports, Wikidata, Natural Earth or any other source. Data provided as is, without warranty. ZCTAs are Census approximations and are not USPS ZIP Codes. Support: gb1@mail.grokbot.com. See also the terms, refund policy and privacy policy.